diff --git a/core/captcha.php b/core/captcha.php
index 56b9ec50..c731ab6e 100644
--- a/core/captcha.php
+++ b/core/captcha.php
@@ -3,6 +3,8 @@
 * CAPTCHA abstraction                                                       *
 \* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
+use ReCaptcha\ReCaptcha;
+
 function captcha_get_html(): string
 {
     global $config, $user;
@@ -37,7 +39,7 @@ function captcha_check(): bool
     if ($user->is_anonymous() && $config->get_bool("comment_captcha")) {
         $r_privatekey = $config->get_string('api_recaptcha_privkey');
         if (!empty($r_privatekey)) {
-            $recaptcha = new \ReCaptcha\ReCaptcha($r_privatekey);
+            $recaptcha = new ReCaptcha($r_privatekey);
             $resp = $recaptcha->verify($_POST['g-recaptcha-response'], $_SERVER['REMOTE_ADDR']);
 
             if (!$resp->isSuccess()) {
diff --git a/core/extension.php b/core/extension.php
index d2bea604..d464b578 100644
--- a/core/extension.php
+++ b/core/extension.php
@@ -395,7 +395,7 @@ abstract class DataHandlerExtension extends Extension
                     throw new UploadException("Unable to scan media properties: ".$e->getMessage());
                 }
 
-                $ire = send_event(new ImageReplaceEvent($image_id, $image));
+                send_event(new ImageReplaceEvent($image_id, $image));
                 $event->image_id = $image_id;
             } else {
                 $image = $this->create_image_from_data(warehouse_path(Image::IMAGE_DIR, $event->hash), $event->metadata);
@@ -453,6 +453,7 @@ abstract class DataHandlerExtension extends Extension
     {
         global $page;
         if ($this->supported_ext($event->image->ext)) {
+            /** @noinspection PhpPossiblePolymorphicInvocationInspection */
             $this->theme->display_image($page, $event->image);
         }
     }
diff --git a/core/install.php b/core/install.php
index f9219cc1..e85299e4 100644
--- a/core/install.php
+++ b/core/install.php
@@ -61,8 +61,10 @@ function get_dsn()
 {
     if (file_exists("data/config/auto_install.conf.php")) {
         $dsn = null;
+        /** @noinspection PhpIncludeInspection */
         require_once "data/config/auto_install.conf.php";
     } elseif (@$_POST["database_type"] == DatabaseDriver::SQLITE) {
+        /** @noinspection PhpUnhandledExceptionInspection */
         $id = bin2hex(random_bytes(5));
         $dsn = "sqlite:data/shimmie.{$id}.sqlite";
     } elseif (isset($_POST['database_type']) && isset($_POST['database_host']) && isset($_POST['database_user']) && isset($_POST['database_name'])) {
@@ -136,7 +138,7 @@ function ask_questions()
 
     <h3>Database Install</h3>
     <form action="index.php" method="POST">
-        <center>
+        <div style="text-align: center;">
             <table class='form'>
                 <tr>
                     <th>Type:</th>
@@ -164,7 +166,7 @@ function ask_questions()
                 </tr>
                 <tr><td colspan="2"><input type="submit" value="Go!"></td></tr>
             </table>
-        </center>
+        </div>
         <script>
         document.addEventListener('DOMContentLoaded', update_qs);
         function q(n) {
@@ -342,7 +344,7 @@ function write_config($dsn)
 function exit_with_page($title, $body, $code=0)
 {
     print("<!DOCTYPE html>
-<html>
+<html lang='en'>
 	<head>
 		<title>Shimmie Installer</title>
 		<link rel=\"shortcut icon\" href=\"ext/static_files/static/favicon.ico\">
diff --git a/core/polyfills.php b/core/polyfills.php
index f78a4ced..9c7b2edb 100644
--- a/core/polyfills.php
+++ b/core/polyfills.php
@@ -341,6 +341,7 @@ function get_extension(?string $mime_type): ?string
     return ($ext ? $ext : null);
 }
 
+/** @noinspection PhpUnhandledExceptionInspection */
 function getSubclassesOf(string $parent)
 {
     $result = [];
diff --git a/core/tests/basepage.test.php b/core/tests/basepage.test.php
index d1f98531..03c9c34c 100644
--- a/core/tests/basepage.test.php
+++ b/core/tests/basepage.test.php
@@ -1,7 +1,10 @@
 <?php declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
 require_once "core/basepage.php";
 
-class BasePageTest extends \PHPUnit\Framework\TestCase
+class BasePageTest extends TestCase
 {
     public function test_page()
     {
diff --git a/core/tests/block.test.php b/core/tests/block.test.php
index 41a1de25..bdaa1e97 100644
--- a/core/tests/block.test.php
+++ b/core/tests/block.test.php
@@ -1,7 +1,10 @@
 <?php declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
 require_once "core/block.php";
 
-class BlockTest extends \PHPUnit\Framework\TestCase
+class BlockTest extends TestCase
 {
     public function test_basic()
     {
diff --git a/core/tests/polyfills.test.php b/core/tests/polyfills.test.php
index 00073668..84c3eea0 100644
--- a/core/tests/polyfills.test.php
+++ b/core/tests/polyfills.test.php
@@ -1,7 +1,10 @@
 <?php declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
 require_once "core/polyfills.php";
 
-class PolyfillsTest extends \PHPUnit\Framework\TestCase
+class PolyfillsTest extends TestCase
 {
     public function test_html_escape()
     {
diff --git a/core/tests/tag.test.php b/core/tests/tag.test.php
index 2afd2752..ef8e947f 100644
--- a/core/tests/tag.test.php
+++ b/core/tests/tag.test.php
@@ -1,7 +1,10 @@
 <?php declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
 require_once "core/imageboard/tag.php";
 
-class TagTest extends \PHPUnit\Framework\TestCase
+class TagTest extends TestCase
 {
     public function test_caret()
     {
diff --git a/core/tests/urls.test.php b/core/tests/urls.test.php
index 6dff4d82..b6ff90f0 100644
--- a/core/tests/urls.test.php
+++ b/core/tests/urls.test.php
@@ -1,7 +1,10 @@
 <?php declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
 require_once "core/urls.php";
 
-class UrlsTest extends \PHPUnit\Framework\TestCase
+class UrlsTest extends TestCase
 {
     public function test_make_link()
     {
diff --git a/core/tests/util.test.php b/core/tests/util.test.php
index be002783..94f2273b 100644
--- a/core/tests/util.test.php
+++ b/core/tests/util.test.php
@@ -1,7 +1,10 @@
 <?php declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
 require_once "core/util.php";
 
-class UtilTest extends \PHPUnit\Framework\TestCase
+class UtilTest extends TestCase
 {
     public function test_warehouse_path()
     {
diff --git a/core/user.php b/core/user.php
index 56b57471..75406597 100644
--- a/core/user.php
+++ b/core/user.php
@@ -214,7 +214,7 @@ class User
                 $d = urlencode($config->get_string("avatar_gravatar_default"));
                 $r = $config->get_string("avatar_gravatar_rating");
                 $cb = date("Y-m-d");
-                return "<img class=\"avatar gravatar\" src=\"https://www.gravatar.com/avatar/$hash.jpg?s=$s&d=$d&r=$r&cacheBreak=$cb\">";
+                return "<img alt='avatar' class=\"avatar gravatar\" src=\"https://www.gravatar.com/avatar/$hash.jpg?s=$s&d=$d&r=$r&cacheBreak=$cb\">";
             }
         }
         return "";
diff --git a/core/util.php b/core/util.php
index 51399e72..c2913047 100644
--- a/core/util.php
+++ b/core/util.php
@@ -468,7 +468,9 @@ function get_debug_info(): string
 * Request initialisation stuff                                              *
 \* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-/** @privatesection */
+/** @privatesection
+ * @noinspection PhpIncludeInspection
+ */
 
 function require_all(array $files): void
 {
@@ -493,7 +495,7 @@ function _load_theme_files()
 
 function _sanitise_environment(): void
 {
-    global $_tracer, $tracer_enabled;
+    global $tracer_enabled;
 
     $min_php = "7.3";
     if (version_compare(phpversion(), $min_php, ">=") === false) {
@@ -524,7 +526,6 @@ date and you should plan on moving elsewhere.
     // so to prevent running out of memory during complex operations code that uses it should
     // check if tracer output is enabled before making use of it.
     $tracer_enabled = constant('TRACE_FILE')!==null;
-    $_tracer = new EventTracer();
 
     ob_start();
 
@@ -553,12 +554,14 @@ function _get_themelet_files(string $_theme): array
 
 /**
  * Used to display fatal errors to the web user.
+ * @noinspection PhpPossiblePolymorphicInvocationInspection
  */
 function _fatal_error(Exception $e): void
 {
     $version = VERSION;
     $message = $e->getMessage();
     $phpver = phpversion();
+    $query = is_subclass_of($e, "SCoreException") ? $e->query : null;
 
     //$hash = exec("git rev-parse HEAD");
     //$h_hash = $hash ? "<p><b>Hash:</b> $hash" : "";
@@ -576,13 +579,13 @@ function _fatal_error(Exception $e): void
 
         print("Message: $message\n");
 
-        if (isset($e->query)) {
-            print("Query:   {$e->query}\n");
+        if ($query) {
+            print("Query:   {$query}\n");
         }
 
         print("Version: $version (on $phpver)\n");
     } else {
-        $q = (!isset($e->query) || is_null($e->query)) ? "" : "<p><b>Query:</b> " . html_escape($e->query);
+        $q = $query ? "" : "<p><b>Query:</b> " . html_escape($query);
         header("HTTP/1.0 500 Internal Error");
         echo '
 <!doctype html>
diff --git a/ext/admin/main.php b/ext/admin/main.php
index 36bb3198..6e41e952 100644
--- a/ext/admin/main.php
+++ b/ext/admin/main.php
@@ -1,4 +1,5 @@
-<?php declare(strict_types=1);
+<?php /** @noinspection PhpUnusedPrivateMethodInspection */
+declare(strict_types=1);
 
 /**
  * Sent when the admin page is ready to be added to
diff --git a/ext/admin/theme.php b/ext/admin/theme.php
index 8e8e9b34..6979aa59 100644
--- a/ext/admin/theme.php
+++ b/ext/admin/theme.php
@@ -37,7 +37,7 @@ class AdminPageTheme extends Themelet
      */
     public function display_form()
     {
-        global $page, $database;
+        global $page;
 
         $html = "";
         $html .= $this->button("All tags to lowercase", "lowercase_all_tags", true);
diff --git a/ext/autocomplete/lib/tagit.ui-zendesk.css b/ext/autocomplete/lib/tagit.ui-zendesk.css
index b91181bf..18982864 100644
--- a/ext/autocomplete/lib/tagit.ui-zendesk.css
+++ b/ext/autocomplete/lib/tagit.ui-zendesk.css
@@ -14,8 +14,7 @@ ul.tagit li.tagit-choice {
     -webkit-border-radius: 6px;
     border: 1px solid #CAD8F3;
 
-    background: none;
-    background-color: #DEE7F8;
+    background: #DEE7F8 none;
 
     font-weight: normal;
 }
diff --git a/ext/bbcode/main.php b/ext/bbcode/main.php
index 8cc994b8..52ddcc4b 100644
--- a/ext/bbcode/main.php
+++ b/ext/bbcode/main.php
@@ -19,7 +19,7 @@ class BBCode extends FormatterExtension
         $text = preg_replace('!\[url=((?:https?|ftp|irc|mailto)://.*?)\](.*?)\[/url\]!s', '<a href="$1">$2</a>', $text);
         $text = preg_replace('!\[url\]((?:https?|ftp|irc|mailto)://.*?)\[/url\]!s', '<a href="$1">$1</a>', $text);
         $text = preg_replace('!\[email\](.*?)\[/email\]!s', '<a href="mailto:$1">$1</a>', $text);
-        $text = preg_replace('!\[img\](https?:\/\/.*?)\[/img\]!s', '<img src="$1">', $text);
+        $text = preg_replace('!\[img\](https?:\/\/.*?)\[/img\]!s', '<img alt="user image" src="$1">', $text);
         $text = preg_replace('!\[\[([^\|\]]+)\|([^\]]+)\]\]!s', '<a href="'.make_link('wiki/$1').'">$2</a>', $text);
         $text = preg_replace('!\[\[([^\]]+)\]\]!s', '<a href="'.make_link('wiki/$1').'">$1</a>', $text);
         $text = preg_replace("!\n\s*\n!", "\n\n", $text);
diff --git a/ext/blotter/theme.php b/ext/blotter/theme.php
index 809af38d..c1d38d37 100644
--- a/ext/blotter/theme.php
+++ b/ext/blotter/theme.php
@@ -121,8 +121,8 @@ class BlotterTheme extends Themelet
             $clean_date = date("y/m/d", strtotime($messy_date));
             $entry_text = $entries[$i]['entry_text'];
             if ($entries[$i]['important'] == 'Y') {
-                $i_open = "<font color='#{$i_color}'>";
-                $i_close="</font>";
+                $i_open = "<span style='color: #$i_color;'>";
+                $i_close="</span>";
             }
             $html .= "{$i_open}{$clean_date} - {$entry_text}{$i_close}<br /><br />";
         }
@@ -149,8 +149,8 @@ class BlotterTheme extends Themelet
             $clean_date = date("m/d/y", strtotime($messy_date));
             $entry_text = $entries[$i]['entry_text'];
             if ($entries[$i]['important'] == 'Y') {
-                $i_open = "<font color='#{$i_color}'>";
-                $i_close="</font>";
+                $i_open = "<span style='color: #$i_color'>";
+                $i_close="</span>";
             }
             $entries_list .= "<li>{$i_open}{$clean_date} - {$entry_text}{$i_close}</li>";
         }
diff --git a/ext/comment/style.css b/ext/comment/style.css
index 74aa19e6..373b34f4 100644
--- a/ext/comment/style.css
+++ b/ext/comment/style.css
@@ -14,11 +14,11 @@
 	background: #DDD;
 	border: 1px solid #CCC;
 	position: absolute;
-	top: 0px;
+	top: 0;
 	left: -195px;
 	width: 180px;
 	z-index: 1;
-	box-shadow: 0px 0px 4px #000;
+	box-shadow: 0 0 4px #000;
 	border-radius: 4px;
 }
 .comment:hover .info {
@@ -39,6 +39,6 @@
 	background: none;
 	border: none;
 	box-shadow: none;
-	margin: 0px;
-	padding: 0px;
+	margin: 0;
+	padding: 0;
 }
diff --git a/ext/comment/test.php b/ext/comment/test.php
index 38f7abe0..9541d6fa 100644
--- a/ext/comment/test.php
+++ b/ext/comment/test.php
@@ -94,13 +94,13 @@ class CommentListTest extends ShimmiePHPUnitTestCase
 
         # make a comment
         send_event(new CommentPostingEvent($image_id, $user, "Test Comment ASDFASDF"));
-        $page = $this->get_page("post/view/$image_id");
+        $this->get_page("post/view/$image_id");
         $this->assert_text("ASDFASDF");
 
         # delete a comment
         $comment_id = (int)$database->get_one("SELECT id FROM comments");
         send_event(new CommentDeletionEvent($comment_id));
-        $page = $this->get_page("post/view/$image_id");
+        $this->get_page("post/view/$image_id");
         $this->assert_no_text("ASDFASDF");
     }
 }
diff --git a/ext/comment/theme.php b/ext/comment/theme.php
index 5d6ac5cd..9c969783 100644
--- a/ext/comment/theme.php
+++ b/ext/comment/theme.php
@@ -242,7 +242,7 @@ class CommentListTheme extends Themelet
             if (!empty($comment->owner_email)) {
                 $hash = md5(strtolower($comment->owner_email));
                 $cb = date("Y-m-d");
-                $h_avatar = "<img src=\"//www.gravatar.com/avatar/$hash.jpg?cacheBreak=$cb\"><br>";
+                $h_avatar = "<img alt='avatar' src=\"//www.gravatar.com/avatar/$hash.jpg?cacheBreak=$cb\"><br>";
             }
             $h_reply = " - <a href='javascript: replyTo($i_image_id, $i_comment_id, \"$h_name\")'>Reply</a>";
             $h_ip = $user->can(Permissions::VIEW_IP) ? "<br>".show_ip($comment->poster_ip, "Comment posted {$comment->posted}") : "";
diff --git a/ext/danbooru_api/main.php b/ext/danbooru_api/main.php
index ec3bf9f8..d85319da 100644
--- a/ext/danbooru_api/main.php
+++ b/ext/danbooru_api/main.php
@@ -97,6 +97,7 @@ class DanbooruApi extends Extension
         elseif (false && isset($_GET['tags'])) {
             $start = isset($_GET['after_id']) ? int_escape($_GET['offset']) : 0;
             $tags = Tag::explode($_GET['tags']);
+            assert(!is_null($start) && !is_null($tags));
         } else {
             $start = isset($_GET['after_id']) ? int_escape($_GET['offset']) : 0;
             $sqlresult = $database->get_all(
diff --git a/ext/downtime/theme.php b/ext/downtime/theme.php
index fc6c59cc..c1a752bc 100644
--- a/ext/downtime/theme.php
+++ b/ext/downtime/theme.php
@@ -9,7 +9,7 @@ class DowntimeTheme extends Themelet
     {
         $page->add_block(new Block(
             "Downtime",
-            "<span style='font-size: 1.5em'><b><center>DOWNTIME MODE IS ON!</center></b></span>",
+            "<span style='font-size: 1.5em; text-align: center;'><b>DOWNTIME MODE IS ON!</b></span>",
             "left",
             0
         ));
@@ -30,7 +30,7 @@ class DowntimeTheme extends Themelet
         $page->set_code(503);
         $page->set_data(
             <<<EOD
-<html>
+<html lang="en">
 	<head>
 		<title>Downtime</title>
 		<link rel="stylesheet" href="$data_href/themes/$theme_name/style.css" type="text/css">
@@ -38,7 +38,7 @@ class DowntimeTheme extends Themelet
 	<body>
 		<div id="downtime">
 			<section>
-				<h1><center>Down for Maintenance</center></h1>
+				<h1 style="text-align: center;">Down for Maintenance</h1>
 				<div id="message" class="blockbody">
 					$message
 				</div>
diff --git a/ext/emoticons/main.php b/ext/emoticons/main.php
index cfd5bf22..38563341 100644
--- a/ext/emoticons/main.php
+++ b/ext/emoticons/main.php
@@ -9,7 +9,7 @@ class Emoticons extends FormatterExtension
     public function format(string $text): string
     {
         $data_href = get_base_href();
-        $text = preg_replace("/:([a-z]*?):/s", "<img src='$data_href/ext/emoticons/default/\\1.gif'>", $text);
+        $text = preg_replace("/:([a-z]*?):/s", "<img alt='\1' src='$data_href/ext/emoticons/default/\\1.gif'>", $text);
         return $text;
     }
 
diff --git a/ext/emoticons_list/theme.php b/ext/emoticons_list/theme.php
index c1f6aac6..17fb1f8a 100644
--- a/ext/emoticons_list/theme.php
+++ b/ext/emoticons_list/theme.php
@@ -5,13 +5,13 @@ class EmoticonListTheme extends Themelet
     {
         global $page;
         $data_href = get_base_href();
-        $html = "<html><head><title>Emoticon list</title></head><body>";
+        $html = "<html lang='en'><head><title>Emoticon list</title></head><body>";
         $html .= "<table><tr>";
         $n = 1;
         foreach ($list as $item) {
             $pathinfo = pathinfo($item);
             $name = $pathinfo["filename"];
-            $html .= "<td><img src='$data_href/$item'> :$name:</td>";
+            $html .= "<td><img alt='$name' src='$data_href/$item'> :$name:</td>";
             if ($n++ % 3 == 0) {
                 $html .= "</tr><tr>";
             }
diff --git a/ext/handle_cbz/theme.php b/ext/handle_cbz/theme.php
index 426a1aad..382f4401 100644
--- a/ext/handle_cbz/theme.php
+++ b/ext/handle_cbz/theme.php
@@ -13,7 +13,7 @@ class CBZFileHandlerTheme extends Themelet
                 </div>
                 <div id='comicView'>
                     <a id='comicPrev'><span>&lt;</span></a>
-                    <img id='comicPage' src='{$data_href}/ext/handle_cbz/spinner.gif' />
+                    <img alt='comic' id='comicPage' src='{$data_href}/ext/handle_cbz/spinner.gif' />
                     <a id='comicNext'><span>&gt;</span></a>
                 </div>
             </div>
diff --git a/ext/handle_svg/theme.php b/ext/handle_svg/theme.php
index 0507b1ee..e22bdb93 100644
--- a/ext/handle_svg/theme.php
+++ b/ext/handle_svg/theme.php
@@ -7,7 +7,14 @@ class SVGFileHandlerTheme extends Themelet
         $ilink = make_link("get_svg/{$image->id}/{$image->id}.svg");
         //		$ilink = $image->get_image_link();
         $html = "
-			<img src='$ilink' id='main_image' class='shm-main-image' data-width='{$image->width}' data-height='{$image->height}' />
+			<img
+			    alt='main image'
+			    src='$ilink'
+			    id='main_image'
+			    class='shm-main-image'
+			    data-width='{$image->width}'
+			    data-height='{$image->height}'
+			    />
 		";
         $page->add_block(new Block("Image", $html, "main", 10));
     }
diff --git a/ext/handle_video/theme.php b/ext/handle_video/theme.php
index 168d34ce..e69c3555 100644
--- a/ext/handle_video/theme.php
+++ b/ext/handle_video/theme.php
@@ -13,15 +13,6 @@ class VideoFileHandlerTheme extends Themelet
         $loop = $config->get_bool("video_playback_loop");
         $player = make_link('vendor/bower-asset/mediaelement/build/flashmediaelement.swf');
 
-        $width="auto";
-        if ($image->width>1) {
-            $width = $image->width."px";
-        }
-        $height="auto";
-        if ($image->height>1) {
-            $height = $image->height."px";
-        }
-
         $html = "Video not playing? <a href='$ilink'>Click here</a> to download the file.<br/>";
 
         //Browser media format support: https://developer.mozilla.org/en-US/docs/Web/HTML/Supported_media_formats
@@ -46,7 +37,7 @@ class VideoFileHandlerTheme extends Themelet
                                 . "&poster={$thumb_url}"
                                 . "&file={$full_url}"
                                 . "&loop=" . ($loop ? 'true' : 'false') . "\" />
-							<img src=\"{$thumb_url}\" />
+							<img alt='thumb' src=\"{$thumb_url}\" />
 						</object>";
 
             if ($ext == "flv") {
@@ -57,7 +48,7 @@ class VideoFileHandlerTheme extends Themelet
                 $loop     = ($loop ? ' loop' : '');
 
                 $html .= "
-					<video controls class='shm-main-image' id='main_image' alt='main image' poster='$thumb_url' {$autoplay} {$loop} 
+					<video controls class='shm-main-image' id='main_image' alt='main image' poster='$thumb_url' {$autoplay} {$loop}
 					style='max-width: 100%'>
 						<source src='{$ilink}' type='{$supportedExts[$ext]}'>
 
diff --git a/ext/help_pages/main.php b/ext/help_pages/main.php
index 69043ba6..a3fe8290 100644
--- a/ext/help_pages/main.php
+++ b/ext/help_pages/main.php
@@ -64,7 +64,6 @@ class HelpPages extends Extension
             } else {
                 $page->set_mode(PageMode::PAGE);
                 $name = $event->get_arg(0);
-                $title = $name;
                 if (array_key_exists($name, $pages)) {
                     $title = $pages[$name];
                 } else {
diff --git a/ext/home/style.css b/ext/home/style.css
index dba7e859..234f512d 100644
--- a/ext/home/style.css
+++ b/ext/home/style.css
@@ -1,4 +1,4 @@
-div#front-page h1 {font-size: 4em; margin-top: 2em; margin-bottom: 0px; text-align: center; border: none; background: none; box-shadow: none; -webkit-box-shadow: none; -moz-box-shadow: none;}
+div#front-page h1 {font-size: 4em; margin-top: 2em; margin-bottom: 0; text-align: center; border: none; background: none; box-shadow: none; -webkit-box-shadow: none; -moz-box-shadow: none;}
 div#front-page {text-align:center;}
 .space {margin-bottom: 1em;}
 div#front-page div#links a {margin: 0 0.5em;}
diff --git a/ext/home/theme.php b/ext/home/theme.php
index dc816d6f..7d9f01db 100644
--- a/ext/home/theme.php
+++ b/ext/home/theme.php
@@ -10,7 +10,7 @@ class HomeTheme extends Themelet
         $page->set_data(
             <<<EOD
 <!doctype html>
-<html>
+<html lang="en">
 	<head>
 		<title>$sitename</title>
 		<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
diff --git a/ext/image_hash_ban/test.php b/ext/image_hash_ban/test.php
index be6f6857..8412ce1a 100644
--- a/ext/image_hash_ban/test.php
+++ b/ext/image_hash_ban/test.php
@@ -37,7 +37,7 @@ class ImageBanTest extends ShimmiePHPUnitTestCase
         $this->assertEquals(200, $page->code);
     }
 
-    public function onNotSuccessfulTest(\Throwable $t): void
+    public function onNotSuccessfulTest(Throwable $t): void
     {
         send_event(new RemoveImageHashBanEvent($this->hash));
         parent::onNotSuccessfulTest($t); // TODO: Change the autogenerated stub
diff --git a/ext/index/test.php b/ext/index/test.php
index 5dac2e88..67771800 100644
--- a/ext/index/test.php
+++ b/ext/index/test.php
@@ -172,7 +172,6 @@ class IndexTest extends ShimmiePHPUnitTestCase
     /** @depends testUpload */
     public function testMixedSearchTagMeta($image_ids)
     {
-        global $database;
         // multiple tags, many results
         $this->assert_search_results(["computer", "size=640x480"], [$image_ids[1], $image_ids[0]]);
     }
diff --git a/ext/link_image/theme.php b/ext/link_image/theme.php
index 2b1f40de..b70c7dd0 100644
--- a/ext/link_image/theme.php
+++ b/ext/link_image/theme.php
@@ -77,7 +77,7 @@ class LinkImageTheme extends Themelet
     {
         switch ($type) {
             case "html":
-                $text = "<img src=\"$src\" />";
+                $text = "<img src=\"$src\" alt=\"\" />";
                 break;
             case "ubb":
                 $text = "[img]".$src."[/img]";
diff --git a/ext/notes/style.css b/ext/notes/style.css
index c4b00f4f..ccdb7e97 100644
--- a/ext/notes/style.css
+++ b/ext/notes/style.css
@@ -1,87 +1,87 @@
-.note {
-	display: block;
-
-	background-color: #FFE;
-	border: 1px dashed black;
-	overflow: hidden; 
-	position: absolute; 
-	z-index: 0;
-
-	filter:alpha(opacity=50);
-	-moz-opacity:0.5;
-	-khtml-opacity: 0.5;
-	opacity: 0.5;
-}
-
-.notep {
-	display: none; 
-	color: #412a21;
-	background-color: #fffdef; 
-	border: #412a21 1px solid; 
-	font-size: 8pt; 
-	margin-top: 0px; 
-	padding: 2px;
-	position: absolute;
-	width: 175px;
-} 
-
-#noteform, #noteEditForm {
-	display: none;
-	position: absolute;
-	width: 250px;
-}
-
-#noteform textarea, #noteEditForm textarea {
-	width: 100%;
-}
-
-/*
- * imgAreaSelect default style
- */
-
-.imgareaselect-border1 {
-	background: url(border-v.gif) repeat-y left top;
-}
-
-.imgareaselect-border2 {
-    background: url(border-h.gif) repeat-x left top;
-}
-
-.imgareaselect-border3 {
-    background: url(border-v.gif) repeat-y right top;
-}
-
-.imgareaselect-border4 {
-    background: url(border-h.gif) repeat-x left bottom;
-}
-
-.imgareaselect-border1, .imgareaselect-border2,
-.imgareaselect-border3, .imgareaselect-border4 {
-    filter: alpha(opacity=50);
-	opacity: 0.5;
-}
-
-.imgareaselect-handle {
-    background-color: #fff;
-    border: solid 1px #000;
-    filter: alpha(opacity=50);
-    opacity: 0.5;
-}
-
-.imgareaselect-outer {
-    /*background-color: #000;*/
-    filter: alpha(opacity=50);
-    opacity: 0.5;
-}
-
-.imgareaselect-selection {  
-}
-
-/* Makes sure the note block is hidden */
-section#note_system {
-	height: 0;
-}
-section#note_system > .blockbody {
-	padding: 0;
-	border: 0;
-}
+.note {
+	display: block;
+
+	background-color: #FFE;
+	border: 1px dashed black;
+	overflow: hidden;
+	position: absolute;
+	z-index: 0;
+
+	filter:alpha(opacity=50);
+	-moz-opacity:0.5;
+	-khtml-opacity: 0.5;
+	opacity: 0.5;
+}
+
+.notep {
+	display: none;
+	color: #412a21;
+	background-color: #fffdef;
+	border: #412a21 1px solid;
+	font-size: 8pt;
+	margin-top: 0;
+	padding: 2px;
+	position: absolute;
+	width: 175px;
+}
+
+#noteform, #noteEditForm {
+	display: none;
+	position: absolute;
+	width: 250px;
+}
+
+#noteform textarea, #noteEditForm textarea {
+	width: 100%;
+}
+
+/*
+ * imgAreaSelect default style
+ */
+
+.imgareaselect-border1 {
+	background: url(border-v.gif) repeat-y left top;
+}
+
+.imgareaselect-border2 {
+    background: url(border-h.gif) repeat-x left top;
+}
+
+.imgareaselect-border3 {
+    background: url(border-v.gif) repeat-y right top;
+}
+
+.imgareaselect-border4 {
+    background: url(border-h.gif) repeat-x left bottom;
+}
+
+.imgareaselect-border1, .imgareaselect-border2,
+.imgareaselect-border3, .imgareaselect-border4 {
+    filter: alpha(opacity=50);
+	opacity: 0.5;
+}
+
+.imgareaselect-handle {
+    background-color: #fff;
+    border: solid 1px #000;
+    filter: alpha(opacity=50);
+    opacity: 0.5;
+}
+
+.imgareaselect-outer {
+    /*background-color: #000;*/
+    filter: alpha(opacity=50);
+    opacity: 0.5;
+}
+
+.imgareaselect-selection {
+}
+
+/* Makes sure the note block is hidden */
+section#note_system {
+	height: 0;
+}
+section#note_system > .blockbody {
+	padding: 0;
+	border: 0;
+}
diff --git a/ext/numeric_score/theme.php b/ext/numeric_score/theme.php
index 4023f185..da9b1d9c 100644
--- a/ext/numeric_score/theme.php
+++ b/ext/numeric_score/theme.php
@@ -80,11 +80,9 @@ class NumericScoreTheme extends Themelet
         $f_dte = make_link("popular_by_".$dte[3]."?".date($dte[2], (strtotime('+1 '.$dte[3], strtotime($dte[0])))));
 
         $html = "\n".
-            "<center>\n".
-            "	<h3>\n".
-            "		<a href='{$b_dte}'>&laquo;</a> {$dte[1]} <a href='{$f_dte}'>&raquo;</a>\n".
-            "	</h3>\n".
-            "</center>\n".
+            "<h3 style='text-align: center;'>\n".
+            "	<a href='{$b_dte}'>&laquo;</a> {$dte[1]} <a href='{$f_dte}'>&raquo;</a>\n".
+            "</h3>\n".
             "<br/>\n".$pop_images;
 
 
diff --git a/ext/ouroboros_api/main.php b/ext/ouroboros_api/main.php
index dfbcdcba..f0f983bf 100644
--- a/ext/ouroboros_api/main.php
+++ b/ext/ouroboros_api/main.php
@@ -239,6 +239,7 @@ class OuroborosPost extends _SafeOuroborosImage
     /**
      * Initialize an OuroborosPost for creation
      * Mainly just acts as a wrapper and validation layer
+     * @noinspection PhpMissingParentConstructorInspection
      */
     public function __construct(array $post, string $md5 = '')
     {
diff --git a/ext/rating/main.php b/ext/rating/main.php
index a03314ab..90386cb5 100644
--- a/ext/rating/main.php
+++ b/ext/rating/main.php
@@ -58,6 +58,7 @@ add_rating(new ImageRating("?", "Unrated", "unrated", 99999));
 add_rating(new ImageRating("s", "Safe", "safe", 0));
 add_rating(new ImageRating("q", "Questionable", "questionable", 500));
 add_rating(new ImageRating("e", "Explicit", "explicit", 1000));
+/** @noinspection PhpIncludeInspection */
 @include_once "data/config/ratings.conf.php";
 
 class RatingSetEvent extends Event
diff --git a/ext/regen_thumb/theme.php b/ext/regen_thumb/theme.php
index d5fc52c7..5463713a 100644
--- a/ext/regen_thumb/theme.php
+++ b/ext/regen_thumb/theme.php
@@ -49,7 +49,7 @@ class RegenThumbTheme extends Themelet
                 <tr><th><label for='regen_thumb_force'>Force</label></th><td><input type='checkbox' name='regen_thumb_force' id='regen_thumb_force' value='true' /></td></tr>
                 <tr><th><label for='regen_thumb_limit'>Limit</label></th><td><input type='number' name='regen_thumb_limit' id='regen_thumb_limit' value='1000' /></td></tr>
                 <tr><th><label for='regen_thumb_type'>Type</label></th><td>
-                    <select name='regen_thumb_type' id='regen_thumb_type' value='1000'>
+                    <select name='regen_thumb_type' id='regen_thumb_type'>
                         <option value=''>All</option>
                         ".implode($types)."
                     </select>
@@ -60,7 +60,7 @@ class RegenThumbTheme extends Themelet
 			<p>".make_form(make_link("admin/delete_thumbs"), "POST", false, "", "return confirm('Are you sure you want to delete all thumbnails?')")."
 				<table class='form'>
                     <tr><th><label for='delete_thumb_type'>Type</label></th><td>
-                        <select name='delete_thumb_type' id='delete_thumb_type' value='1000'>
+                        <select name='delete_thumb_type' id='delete_thumb_type'>
                             <option value=''>All</option>
                             ".implode($types)."
                         </select>
diff --git a/ext/relationships/test.php b/ext/relationships/test.php
index 5ce7fced..b5667073 100644
--- a/ext/relationships/test.php
+++ b/ext/relationships/test.php
@@ -182,6 +182,7 @@ class RelationshipsTest extends ShimmiePHPUnitTestCase
     public function testRemoveParentByTag($imgs)
     {
         [$image_1, $image_2, $image_3] = $imgs;
+        assert(!is_null($image_3));
 
         // check parent is set
         $this->assertEquals($image_2->parent_id, $image_1->id);
diff --git a/ext/rss_images/test.php b/ext/rss_images/test.php
index e6df18e5..00021b77 100644
--- a/ext/rss_images/test.php
+++ b/ext/rss_images/test.php
@@ -4,7 +4,7 @@ class RSSImagesTest extends ShimmiePHPUnitTestCase
     public function testImageFeed()
     {
         $this->log_in_as_user();
-        $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
+        $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
         $this->log_out();
 
         $this->get_page('rss/images');
diff --git a/ext/rule34/style.css b/ext/rule34/style.css
index b4687560..2e394c2d 100644
--- a/ext/rule34/style.css
+++ b/ext/rule34/style.css
@@ -6,10 +6,10 @@ BODY.censored FOOTER {
 }
 .tnc_bg {
 	position: fixed;
-	top: 0px;
-	left: 0px;
-	right: 0px;
-	bottom: 0px;
+	top: 0;
+	left: 0;
+	right: 0;
+	bottom: 0;
 	background: #ACE4A3;
 	opacity: 0.75;
 	z-index: 999999999999999999999;
diff --git a/ext/setup/main.php b/ext/setup/main.php
index d2255ab5..a6263360 100644
--- a/ext/setup/main.php
+++ b/ext/setup/main.php
@@ -271,6 +271,9 @@ class SetupBlock extends Block
 
 class Setup extends Extension
 {
+    /** @var SetupTheme */
+    protected $theme;
+
     public function onInitExt(InitExtEvent $event)
     {
         global $config;
diff --git a/ext/setup/style.css b/ext/setup/style.css
index ad738987..bc460fa4 100644
--- a/ext/setup/style.css
+++ b/ext/setup/style.css
@@ -38,6 +38,6 @@
 	background: none;
 	border: none;
 	box-shadow: none;
-	margin: 0px;
-	padding: 0px;
+	margin: 0;
+	padding: 0;
 }
diff --git a/ext/sitemap/main.php b/ext/sitemap/main.php
index 3598f2b1..afa60714 100644
--- a/ext/sitemap/main.php
+++ b/ext/sitemap/main.php
@@ -107,10 +107,12 @@ class XMLSitemap extends Extension
 
         /* --- Add all other images to sitemap with lower priority --- */
         $otherimages = Image::find_images(51, 10000000, []);
+        $image = null;
         foreach ($otherimages as $arrayid => $image) {
             // create url from image id's
             $otherimages[$arrayid] = "post/view/$image->id";
         }
+        assert(!is_null($image));
         $this->add_sitemap_queue($otherimages, "monthly", "0.6", date("Y-m-d", strtotime($image->posted)));
 
 
diff --git a/ext/static_files/style.css b/ext/static_files/style.css
index 444fa296..593e6742 100644
--- a/ext/static_files/style.css
+++ b/ext/static_files/style.css
@@ -22,7 +22,7 @@ H3[class~="shm-toggler"],
 	cursor: pointer;
 }
 IMG {border: none;}
-FORM {margin: 0px;}
+FORM {margin: 0;}
 IMG.lazy {display: none;}
 
 #flash {
@@ -54,12 +54,12 @@ IMG.lazy {display: none;}
 #installer H1, #installer H3 {
 	background: #DDD;
 	text-align: center;
-	margin: 0px;
+	margin: 0;
 	padding: 2px;
 }
 #installer H1 {
 	border-bottom: 1px solid black;
-	border-radius: 16px 16px 0px 0px;
+	border-radius: 16px 16px 0 0;
 }
 #installer H3 {
 	border-bottom: 1px solid black;
diff --git a/ext/tagger/style.css b/ext/tagger/style.css
index 799877bd..ba9f8407 100644
--- a/ext/tagger/style.css
+++ b/ext/tagger/style.css
@@ -27,7 +27,7 @@
 #tagger_toolbar, #tagger_body {
 	padding:2px 2px 0 2px;
 	border-style:solid;
-	border-width: 0px 2px 0px 2px;	
+	border-width: 0 2px 0 2px;
 }
 #tagger_body {
 	max-height:175px;
@@ -47,7 +47,7 @@
 #tagger_body div {
 	padding-top:2px;
 	margin-top:2px;
-	border-top:1px solid;	
+	border-top:1px solid;
 }
 
 /* Tagger Styling
@@ -69,7 +69,7 @@
 	display: block;
 }
 #tagger_parent tag {
-	font-size:1.25em;	
+	font-size:1.25em;
 	display:block;
 }
 
diff --git a/ext/tips/theme.php b/ext/tips/theme.php
index c1a363c5..7c49a9d9 100644
--- a/ext/tips/theme.php
+++ b/ext/tips/theme.php
@@ -79,7 +79,7 @@ class TipsTheme extends Themelet
                 (
                     empty($tip['image']) ?
                     "<td></td>" :
-                    "<td><img src=".$url.$tip['image']." /></td>"
+                    "<td><img alt='' src=".$url.$tip['image']." /></td>"
                 ).
                 "<td class='left'>".$tip['text']."</td>";
 
diff --git a/ext/upload/bookmarklet.js b/ext/upload/bookmarklet.js
index c03e06a6..29c2945b 100644
--- a/ext/upload/bookmarklet.js
+++ b/ext/upload/bookmarklet.js
@@ -131,18 +131,17 @@ if(document.getElementById("image-container") !== null) {
 
 	if(supext.search(furl.match("[a-zA-Z0-9]+$")[0]) !== -1){
 		history.pushState(history.state, document.title, location.href);
-		var href = ste + furl +
+        location.href = ste + furl +
 			"&tags=" + encodeURIComponent(tag) +
 			"&rating=" + encodeURIComponent(rating) +
 			"&source=" + encodeURIComponent(source);
-		location.href = href;
 	}
 	else{
 		alert(notsup);
 	}
 }
 
-/* 
+/*
  * Shimmie
  *
  * One problem with shimmie is each theme does not show the same info
@@ -184,4 +183,4 @@ else if(document.getElementsByTagName("title")[0].innerHTML.search("Image [0-9.-
 			alert(notsup);
 		}
 	}
-}
\ No newline at end of file
+}
diff --git a/ext/varnish/main.php b/ext/varnish/main.php
index bad33c9b..d927685d 100644
--- a/ext/varnish/main.php
+++ b/ext/varnish/main.php
@@ -17,6 +17,7 @@ class VarnishPurger extends Extension
         $result = curl_exec($ch);
         $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
         curl_close($ch);
+        assert(!is_null($result) && !is_null($httpCode));
         //return $result;
     }
 
diff --git a/ext/view/test.php b/ext/view/test.php
index 96a9f80b..3d6e0cc8 100644
--- a/ext/view/test.php
+++ b/ext/view/test.php
@@ -11,9 +11,6 @@ class ViewImageTest extends ShimmiePHPUnitTestCase
     {
         $this->log_in_as_user();
         $image_id_1 = $this->post_image("tests/pbx_screenshot.jpg", "test");
-        $image_id_2 = $this->post_image("tests/bedroom_workshop.jpg", "test2");
-        $image_id_3 = $this->post_image("tests/favicon.png", "test");
-        $idp1 = $image_id_3 + 1;
 
         $this->get_page("post/view/$image_id_1");
         $this->assert_title("Image $image_id_1: test");
@@ -52,10 +49,8 @@ class ViewImageTest extends ShimmiePHPUnitTestCase
     public function testView404()
     {
         $this->log_in_as_user();
-        $image_id_1 = $this->post_image("tests/pbx_screenshot.jpg", "test");
-        $image_id_2 = $this->post_image("tests/bedroom_workshop.jpg", "test2");
-        $image_id_3 = $this->post_image("tests/favicon.png", "test");
-        $idp1 = $image_id_3 + 1;
+        $image_id_1 = $this->post_image("tests/favicon.png", "test");
+        $idp1 = $image_id_1 + 1;
 
         $this->get_page("post/view/$idp1");
         $this->assert_title('Image not found');
diff --git a/ext/word_filter/test.php b/ext/word_filter/test.php
index f1650521..044615b0 100644
--- a/ext/word_filter/test.php
+++ b/ext/word_filter/test.php
@@ -10,7 +10,7 @@ class WordFilterTest extends ShimmiePHPUnitTestCase
 
     public function _doThings($in, $out)
     {
-        global $user, $_tracer;
+        global $user;
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
         send_event(new CommentPostingEvent($image_id, $user, $in));
diff --git a/index.php b/index.php
index 25ae811e..ecaf6c0e 100644
--- a/index.php
+++ b/index.php
@@ -57,7 +57,7 @@ if (!file_exists("vendor/")) {
     //CHECK: Should we just point to install.php instead? Seems unsafe though.
     print <<<EOD
 <!DOCTYPE html>
-<html>
+<html lang="en">
 	<head>
 		<title>Shimmie Error</title>
 		<link rel="shortcut icon" href="ext/static_files/static/favicon.ico">
@@ -99,6 +99,7 @@ require_once "core/util.php";
 
 global $cache, $config, $database, $user, $page, $_tracer;
 _sanitise_environment();
+$_tracer = new EventTracer();
 $_tracer->begin("Bootstrap");
 _load_core_files();
 $cache = new Cache(CACHE_DSN);
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 75860968..9ad5fe5b 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -1,4 +1,7 @@
 <?php declare(strict_types=1);
+
+use PHPUnit\Framework\TestCase;
+
 chdir(dirname(dirname(__FILE__)));
 require_once "vendor/autoload.php";
 require_once "tests/defines.php";
@@ -14,6 +17,7 @@ if (file_exists("tests/trace.json")) {
 global $cache, $config, $database, $user, $page, $_tracer;
 _sanitise_environment();
 $tracer_enabled = true;
+$_tracer = new EventTracer();
 $_tracer->begin("bootstrap");
 _load_core_files();
 $cache = new Cache(CACHE_DSN);
@@ -34,7 +38,7 @@ send_event(new DatabaseUpgradeEvent());
 send_event(new InitExtEvent());
 $_tracer->end();
 
-abstract class ShimmiePHPUnitTestCase extends \PHPUnit\Framework\TestCase
+abstract class ShimmiePHPUnitTestCase extends TestCase
 {
     protected static $anon_name = "anonymous";
     protected static $admin_name = "demo";
@@ -44,7 +48,7 @@ abstract class ShimmiePHPUnitTestCase extends \PHPUnit\Framework\TestCase
     public static function setUpBeforeClass(): void
     {
         parent::setUpBeforeClass();
-        global $_tracer, $config;
+        global $_tracer;
         $_tracer->begin(get_called_class());
 
         self::create_user(self::$admin_name);
diff --git a/tests/defines.php b/tests/defines.php
index 7d2ccca4..48431eca 100644
--- a/tests/defines.php
+++ b/tests/defines.php
@@ -15,3 +15,4 @@ define("TRACE_THRESHOLD", 0.0);
 define("TIMEZONE", 'UTC');
 define("BASE_HREF", "/test");
 define("CLI_LOG_LEVEL", 50);
+define("STATSD_HOST", null);
diff --git a/themes/default/style.css b/themes/default/style.css
index 0f65cd51..4eefd609 100644
--- a/themes/default/style.css
+++ b/themes/default/style.css
@@ -7,7 +7,7 @@ BODY {
 	background: #EEE;
 	font-family: sans-serif;
 	font-size: 14px;
-	margin: 0px;
+	margin: 0;
 }
 H1 {
 	background: #BBB;
@@ -19,7 +19,7 @@ H1 A {
 }
 H3 {
 	text-align: center;
-	margin: 0px;
+	margin: 0;
 }
 SECTION>H3 {
 	background: #CCC;
@@ -46,7 +46,7 @@ TD {
 	text-align: center;
 }
 
-TABLE.zebra {border-spacing: 0px; border: 2px solid #CCC;}
+TABLE.zebra {border-spacing: 0; border: 2px solid #CCC;}
 TABLE.zebra TD, TABLE.zebra TH {vertical-align: middle; padding: 4px;}
 TABLE.zebra THEAD TD, TABLE.zebra THEAD TH {border-bottom: 2px solid #CCC;}
 TABLE.zebra TFOOT TD, TABLE.zebra TFOOT TH {border-top: 2px solid #CCC;}
@@ -89,11 +89,11 @@ NAV TABLE {
 }
 NAV INPUT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 NAV SELECT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 
 TABLE.tag_list {
diff --git a/themes/futaba/comment.theme.php b/themes/futaba/comment.theme.php
index aa92f52c..d577d784 100644
--- a/themes/futaba/comment.theme.php
+++ b/themes/futaba/comment.theme.php
@@ -37,7 +37,7 @@ class CustomCommentListTheme extends CommentListTheme
                 $comment_html .= $this->comment_to_html($comment, false);
             }
 
-            $html  = "<p style='clear:both'>&nbsp;</p><hr height='1'>";
+            $html  = "<p style='clear:both'>&nbsp;</p><hr >";
             $html .= "File: <a href=\"".make_link("post/view/{$image->id}")."\">$h_filename</a> - ($h_filesize, {$w}x{$h}) - ";
             $html .= html_escape($image->get_tag_list());
             $html .= "<div style='text-align: left'>";
@@ -48,7 +48,7 @@ class CustomCommentListTheme extends CommentListTheme
             $page->add_block(new Block(null, $html, "main", $position++));
         }
     }
-    
+
     public function display_recent_comments(array $comments)
     {
         // sidebar fails in this theme
diff --git a/themes/futaba/style.css b/themes/futaba/style.css
index 9b22277c..4ea6a219 100644
--- a/themes/futaba/style.css
+++ b/themes/futaba/style.css
@@ -10,8 +10,8 @@ BODY {
 	color: #800000;
 	padding-left: 5px;
 	padding-right: 5px;
-	margin-right: 0px;
-	margin-left: 0px;
+	margin-right: 0;
+	margin-left: 0;
 	margin-top: 5px;
 }
 H1 {
@@ -30,7 +30,7 @@ FOOTER {
 
 A, A:visited {text-decoration: none; color: #0000EE;}
 A:hover {text-decoration: underline; color: #DD0000;}
-HR {border: none; border-top: 1px solid #D9BFB7; height: 0px; clear: both;}
+HR {border: none; border-top: 1px solid #D9BFB7; height: 0; clear: both;}
 
 NAV {
 	width: 150px;
@@ -45,11 +45,11 @@ NAV TD {
 }
 NAV INPUT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 NAV SELECT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 NAV H3 {
 	text-align: left;
@@ -92,7 +92,7 @@ TABLE.tag_list>TBODY>TR>TD:after {
 }
 .comment {
 	/*background: #FFFFEE;*/
-	border-width: 0px;
+	border-width: 0;
 }
 .reply, .paginator {
 	margin-bottom: 2px;
@@ -106,7 +106,7 @@ TABLE.tag_list>TBODY>TR>TD:after {
 }
 .reply P {
 	margin-left: 32px;
-	margin-bottom: 0px;
+	margin-bottom: 0;
 }
 
 .setupblock {
diff --git a/themes/lite/style.css b/themes/lite/style.css
index 2b7d61f2..c585dfcf 100644
--- a/themes/lite/style.css
+++ b/themes/lite/style.css
@@ -7,15 +7,15 @@ BODY {
 	background: #F0F7FF;
 	font-family: sans-serif;
 	font-size: 14px;
-	margin: 0px;
+	margin: 0;
 }
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 3                            menu bar                            *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 .menu {
 	border-bottom: 1px solid #C3D2E0;
-	margin-top: 0px;
-	margin-bottom: 0px;
+	margin-top: 0;
+	margin-bottom: 0;
 	padding: 4px;
 	background: #E3EFFA;
 }
@@ -45,7 +45,7 @@ a.tab:hover, a.tab:active, .tab-selected {
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 .sbar {
 	border-bottom: 1px solid #C3D2E0;
-	margin-top: 0px;
+	margin-top: 0;
 	margin-bottom: 16px;
 	padding: 4px;
 	background: #CEDFF0;
@@ -53,8 +53,8 @@ a.tab:hover, a.tab:active, .tab-selected {
 }
 .sfoot {
 	border-top: 1px solid #C3D2E0;
-	margin-top: 0px;
-	margin-bottom: 0px;
+	margin-top: 0;
+	margin-bottom: 0;
 	padding: 4px;
 	background: #CEDFF0;
 	text-align: right;
@@ -83,14 +83,14 @@ a.tab:hover, a.tab:active, .tab-selected {
 	margin:0 0 2px 0; /* top right bottom left */
 	padding:2px 10px;
 	position:relative;
-	left:0px;
+	left:0;
 	width:50%;
 }
 .navtop {
 	top:7px;
 }
 .maintop {
-	top:0px;
+	top:0;
 	margin-top:5px;
 	margin-bottom:5px;
 }
@@ -109,7 +109,7 @@ A, A:hover, A:active, A:visited {
 }
 H3 {
 	text-align: center;
-	margin: 0px;
+	margin: 0;
 }
 THEAD {
 	font-weight: bold;
@@ -132,7 +132,7 @@ CODE {
 	background: #DDD;
 }
 
-TABLE.zebra {border-spacing: 0px; border: 2px solid #C3D2E0;}
+TABLE.zebra {border-spacing: 0; border: 2px solid #C3D2E0;}
 TABLE.zebra TD, TABLE.zebra TH {vertical-align: middle; padding: 4px;}
 TABLE.zebra THEAD TD, TABLE.zebra THEAD TH {border-bottom: 2px solid #C3D2E0;}
 TABLE.zebra TFOOT TD, TABLE.zebra TFOOT TH {border-top: 2px solid #C3D2E0;}
@@ -198,11 +198,11 @@ NAV TD {
 }
 NAV INPUT, nav button {
 	width: 95%;
-	padding: 0px;
+	padding: 0;
 }
 NAV SELECT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 
 #comments P {
@@ -334,7 +334,7 @@ NAV .thumbblock {
 	height: auto;
 }
 NAV .thumb {
-	margin-bottom: 0px;
+	margin-bottom: 0;
 }
 .thumbblock {
 	width: 220px;
diff --git a/themes/lite/wz_tooltip.js b/themes/lite/wz_tooltip.js
index 2ffa50fe..d45ceb01 100644
--- a/themes/lite/wz_tooltip.js
+++ b/themes/lite/wz_tooltip.js
@@ -411,7 +411,7 @@ function tt_MkMainDivHtm()
 {
 	return(
 		'<div id="WzTtDiV"></div>' +
-		(tt_ie56 ? ('<iframe id="WzTtIfRm" src="javascript:false" scrolling="no" frameborder="0" style="filter:Alpha(opacity=0);position:absolute;top:0px;left:0px;display:none;"></iframe>')
+		(tt_ie56 ? ('<iframe id="WzTtIfRm" src="javascript:false" scrolling="no" frameborder="0" style="filter:Alpha(opacity=0);position:absolute;top:0;left:0;display:none;"></iframe>')
 		: '')
 	);
 }
@@ -1305,7 +1305,7 @@ function tt_GetWndCliSiz(s)
 	return(
 		// document.documentElement.client+s functional, returns > 0
 		((db = document.documentElement) && (y = db[sC])) ? y
-		// ... not functional, in which case document.body.client+s 
+		// ... not functional, in which case document.body.client+s
 		// is the clientarea size, fortunately
 		: document.body[sC]
 	);
diff --git a/themes/material/home.theme.php b/themes/material/home.theme.php
index 402b3f3d..595d42ea 100644
--- a/themes/material/home.theme.php
+++ b/themes/material/home.theme.php
@@ -9,7 +9,7 @@ class CustomHomeTheme extends HomeTheme
         $hh = $page->get_all_html_headers();
         $page->set_data(
             <<<EOD
-<html>
+<html lang="en">
 	<head>
 		<title>$sitename</title>
 		<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
diff --git a/themes/material/page.class.php b/themes/material/page.class.php
index 110c28b5..8db7aa12 100644
--- a/themes/material/page.class.php
+++ b/themes/material/page.class.php
@@ -5,7 +5,7 @@ class Page extends BasePage
     {
         global $config;
 
-        list($nav_links, $sub_links) = $this->get_nav_links();
+        // list($nav_links, $sub_links) = $this->get_nav_links();
         $theme_name = $config->get_string(SetupConfig::THEME, 'material');
         $site_name = $config->get_string(SetupConfig::TITLE);
         $data_href = get_base_href();
diff --git a/themes/rule34v2/home.theme.php b/themes/rule34v2/home.theme.php
index cb423c8e..83604879 100644
--- a/themes/rule34v2/home.theme.php
+++ b/themes/rule34v2/home.theme.php
@@ -9,7 +9,7 @@ class CustomHomeTheme extends HomeTheme
         $hh = $page->get_all_html_headers();
         $page->set_data(
             <<<EOD
-<html>
+<html lang="en">
 	<head>
 		<title>$sitename</title>
 		<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
@@ -17,7 +17,7 @@ class CustomHomeTheme extends HomeTheme
 		<meta name="viewport" content="width=device-width, initial-scale=1">
 		$hh
 		<style>
-			div#front-page h1 {font-size: 4em; margin-top: 2em; margin-bottom: 0px; text-align: center; border: none; background: none; box-shadow: none; -webkit-box-shadow: none; -moz-box-shadow: none;}
+			div#front-page h1 {font-size: 4em; margin-top: 2em; margin-bottom: 0; text-align: center; border: none; background: none; box-shadow: none; -webkit-box-shadow: none; -moz-box-shadow: none;}
 			div#front-page {text-align:center;}
 			.space {margin-bottom: 1em;}
 			div#front-page div#links a {margin: 0 0.5em;}
diff --git a/themes/rule34v2/menuh.css b/themes/rule34v2/menuh.css
index 1d96dc42..1077a50d 100644
--- a/themes/rule34v2/menuh.css
+++ b/themes/rule34v2/menuh.css
@@ -15,7 +15,7 @@ a:active.menu { color: #FF0000; text-decoration: none; }
 	top:0;
 	left: 5%;
 	width: 100%;
-	margin: 0px;
+	margin: 0;
 	}
 
 #menuh
@@ -23,7 +23,7 @@ a:active.menu { color: #FF0000; text-decoration: none; }
 	font-size: small;
 	font-family: arial, helvetica, sans-serif;
 	width:100%;
-	margin-top: 0px;
+	margin-top: 0;
 	}
 
 #menuh a.sub_option
@@ -31,36 +31,35 @@ a:active.menu { color: #FF0000; text-decoration: none; }
 	border: 1px solid #555;
 	/*background-image:url(topban.jpg);*/
 	}
-		
+
 #menuh a
 	{
 	text-align: center;
 	background: #ACE4A3;
 	display:block;
 	white-space:nowrap;
-	margin:0;
-	margin-top:0;
-	padding: 0.2em;
+    margin: 0;
+    padding: 0.2em;
 	}
-	
+
 #menuh a, #menuh a:visited	/* menu at rest */
 	{
 	color: #000099;
 	text-decoration:none;
 	}
-	
+
 #menuh a:hover	/* menu at mouse-over  */
 	{
 	color: #000000;
-	}	
-			
+	}
+
 #menuh a.top_parent, #menuh a.top_parent:hover  /* attaches down-arrow to all top-parents */
 	{
 	/*background-image: url(navdown_white.gif);*/
 	background-position: right center;
 	background-repeat: no-repeat;
 	}
-	
+
 #menuh a.parent, #menuh a.parent:hover 	/* attaches side-arrow to all parents */
 	{
 	/*background-image: url(nav_white.gif);*/
diff --git a/themes/rule34v2/page.class.php b/themes/rule34v2/page.class.php
index 2bc88312..b5e9f387 100644
--- a/themes/rule34v2/page.class.php
+++ b/themes/rule34v2/page.class.php
@@ -38,15 +38,15 @@ class Page extends BasePage
             }
         }
 
-        # used in header.inc
         $query = !empty($this->_search_query) ? html_escape(Tag::implode($this->_search_query)) : "";
+        assert(!is_null($query));  # used in header.inc, do not remove :P
         $flash_html = $this->flash ? "<b id='flash'>".nl2br(html_escape(implode("\n", $this->flash)))."</b>" : "";
         $generated = autodate(date('c'));
         $footer_html = $this->footer_html();
 
         print <<<EOD
 <!DOCTYPE html>
-<html>
+<html lang="en">
 	<head>
 		<title>{$this->title}</title>
 		<meta name="description" content="Rule 34, if it exists there is porn of it."/>
@@ -93,10 +93,18 @@ EOD;
 		</article>
 
 		<footer>
-<font size="2px"><a href="http://rule34.paheal.net/wiki/Terms%20of%20use">Terms of use</a> !!! <a href="http://rule34.paheal.net/wiki/Privacy%20policy">Privacy policy</a> !!! <a href="http://rule34.paheal.net/wiki/2257">18 U.S.C. &sect;2257</a><br /></font>
+<span style="font-size: 2px;">
+    <a href="http://rule34.paheal.net/wiki/Terms%20of%20use">Terms of use</a>
+    !!!
+    <a href="http://rule34.paheal.net/wiki/Privacy%20policy">Privacy policy</a>
+    !!!
+    <a href="http://rule34.paheal.net/wiki/2257">18 U.S.C. &sect;2257</a><br />
+</span>
 <hr />
-<font size="2px">BTC: <b>193gutWtgirF7js14ivcXfnfQgXv9n5BZo</b>
-ETH: <b>0x68B88a00e69Bde88E9db1b9fC10b8011226e26aF</b></font>
+<span style="font-size: 2px;">
+    BTC: <b>193gutWtgirF7js14ivcXfnfQgXv9n5BZo</b>
+    ETH: <b>0x68B88a00e69Bde88E9db1b9fC10b8011226e26aF</b>
+</span>
 <hr />
 <br>
 Thank you!
diff --git a/themes/rule34v2/style.css b/themes/rule34v2/style.css
index 99e9ba59..06ccd4c3 100644
--- a/themes/rule34v2/style.css
+++ b/themes/rule34v2/style.css
@@ -7,11 +7,11 @@ BODY {
 	background: url(bg.png) #ACE4A3;
 	font-family: "Arial", sans-serif;
 	font-size: 14px;
-	margin: 0px;
+	margin: 0;
 }
 #header {
 	border-bottom: 1px solid #7EB977;
-	margin-top: 0px;
+	margin-top: 0;
 	margin-bottom: 16px;
 	padding: 8px;
 	background: #ACE4A3;
@@ -19,15 +19,15 @@ BODY {
 }
 H1 {
 	font-size: 5em;
-	margin: 0px;
-	padding: 0px;
+	margin: 0;
+	padding: 0;
 }
 H1 A {
 	color: black;
 }
 H3 {
 	text-align: center;
-	margin: 0px;
+	margin: 0;
 }
 THEAD {
 	font-weight: bold;
@@ -40,9 +40,8 @@ TD {
 #subtitle {
 	width: 256px;
 	font-size: 0.75em;
-	margin: auto;
-	margin-top: -16px;
-	text-align: center;
+    margin: -16px auto auto;
+    text-align: center;
 	border: 1px solid black;
 	border-top: none;
 	background: #DDD;
@@ -56,7 +55,7 @@ TD {
 }
 
 TABLE.zebra {background: #ACE4A3; border-collapse: collapse; border: 1px solid #7EB977;}
-TABLE.zebra TD {font-size: 0.8em;margin: 0px;	border-top: 1px solid #7EB977;	padding: 2px;}
+TABLE.zebra TD {font-size: 0.8em;margin: 0;	border-top: 1px solid #7EB977;	padding: 2px;}
 TABLE.zebra TR:nth-child(odd) {background: #9CD493;}
 TABLE.zebra TR:nth-child(even) {background: #ACE4A3;}
 
@@ -100,11 +99,11 @@ NAV TD {
 }
 NAV INPUT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 NAV SELECT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 
 
@@ -136,13 +135,13 @@ NAV SELECT {
 	background: none;
 	border: none;
 	box-shadow: none;
-	padding: 0px;
+	padding: 0;
 }
 
 #commentlistimage .blockbody .comment,
 #commentlistrecent .blockbody .comment {
-	margin-left: 0px;
-	margin-right: 0px;
+	margin-left: 0;
+	margin-right: 0;
 }
 
 
@@ -162,7 +161,7 @@ ARTICLE TABLE {
 	margin: auto;
 }
 NAV SECTION:first-child H3 {
-	margin-top: 0px;
+	margin-top: 0;
 }
 
 
@@ -209,7 +208,7 @@ SECTION>H3 {
 
 div#twitter_update_list li {
 	list-style:none;
-	padding-bottom:0px;
+	padding-bottom:0;
 	text-align:left;
 	margin-top:5px;
 	margin-bottom:5px;
@@ -241,7 +240,7 @@ div#twitter_update_list li {
 }
 
 UL.tagit {
-	margin: 0px;
+	margin: 0;
 }
 ul.tagit li.tagit-new {
 	width: 50px;
@@ -276,12 +275,12 @@ ul.tagit li.tagit-new {
 
 /* responsive padding */
 @media (max-width: 1024px) {
-	NAV {margin-left: 0px;}
-	ARTICLE {margin-right: 0px; margin-left: 242px;}
+	NAV {margin-left: 0;}
+	ARTICLE {margin-right: 0; margin-left: 242px;}
 }
 @media (max-width: 750px) {
-	NAV {margin-left: 0px;}
-	ARTICLE {margin-right: 0px; margin-left: 250px;}
+	NAV {margin-left: 0;}
+	ARTICLE {margin-right: 0; margin-left: 250px;}
 }
 
 /* responsive navbar */
@@ -293,15 +292,15 @@ ul.tagit li.tagit-new {
 
 	NAV>SECTION>.blockbody,
 	NAV>SECTION>.blockbody>.comment {
-		margin: 0px;
+		margin: 0;
 	}
 	NAV>SECTION>H3 {
-		margin: 0px;
+		margin: 0;
 	}
 
 	BODY.navHidden #menuh-container {display: none;}
 	BODY.navHidden NAV {display: none;}
-	BODY.navHidden ARTICLE {margin-left: 0px;}
+	BODY.navHidden ARTICLE {margin-left: 0;}
 
 /*
 	NAV {
@@ -318,7 +317,7 @@ ul.tagit li.tagit-new {
 	BODY.navHidden {padding-top: 5.4em}
 }
 @media (max-width: 750px) {
-	#header {position: fixed; top: 0px; left: 0px; z-index: 99999999999;}
+	#header {position: fixed; top: 0; left: 0; z-index: 99999999999;}
 	.ui-autocomplete {z-index: 999999999999;}
 	BODY {padding-top: 7em}
 }
@@ -347,7 +346,7 @@ ul.tagit li.tagit-new {
 	#mini-logo {display: table-cell; width: 100px;}
 
 	/* hide nav-search when header-search is sticky */
-	ARTICLE {margin-top: 0px;}
+	ARTICLE {margin-top: 0;}
 	#Navigationleft .blockbody {font-size: 1.5em;}
 	#Navigationleft .blockbody P,
 	#Navigationleft .blockbody FORM
diff --git a/themes/rule34v2/themelet.class.php b/themes/rule34v2/themelet.class.php
index 8d5a5ed8..cd4f0a18 100644
--- a/themes/rule34v2/themelet.class.php
+++ b/themes/rule34v2/themelet.class.php
@@ -3,7 +3,7 @@ class Themelet extends BaseThemelet
 {
     public function build_thumb_html(Image $image): string
     {
-        global $cache, $config, $database, $user;
+        global $cache, $config;
 
         $cached = $cache->get("thumb-block:{$image->id}");
         if ($cached) {
@@ -17,7 +17,7 @@ class Themelet extends BaseThemelet
         $h_tip = html_escape($image->get_tooltip());
         $h_tags = strtolower($image->get_tag_list());
         $h_ext = strtolower($image->ext);
-        
+
         // If file is flash or svg then sets thumbnail to max size.
         if ($image->ext === 'swf' || $image->ext === 'svg') {
             $tsize = get_thumbnail_size($config->get_int('thumb_width'), $config->get_int('thumb_height'));
diff --git a/themes/warm/style.css b/themes/warm/style.css
index b4491f07..2d54532d 100644
--- a/themes/warm/style.css
+++ b/themes/warm/style.css
@@ -7,11 +7,11 @@ BODY {
 	background: url(bg.png);
 	font-family: "Arial", sans-serif;
 	font-size: 14px;
-	margin: 0px;
+	margin: 0;
 }
 HEADER {
 	border-bottom: 1px solid #B89F7C;
-	margin-top: 0px;
+	margin-top: 0;
 	margin-bottom: 16px;
 	padding: 8px;
 	background: #FCD9A9;
@@ -19,15 +19,15 @@ HEADER {
 }
 H1 {
 	font-size: 5em;
-	margin: 0px;
-	padding: 0px;
+	margin: 0;
+	padding: 0;
 }
 H1 A {
 	color: black;
 }
 H3 {
 	text-align: center;
-	margin: 0px;
+	margin: 0;
 }
 THEAD {
 	font-weight: bold;
@@ -50,7 +50,7 @@ CODE {
 	background: #DDD;
 }
 
-TABLE.zebra {border-spacing: 0px; border: 1px solid #B89F7C; }
+TABLE.zebra {border-spacing: 0; border: 1px solid #B89F7C; }
 TABLE.zebra TD, TABLE.zebra TH {vertical-align: middle; padding: 4px;}
 TABLE.zebra THEAD TD, TABLE.zebra THEAD TH {border-bottom: 2px solid #B89F7C;}
 TABLE.zebra TFOOT TD, TABLE.zebra TFOOT TH {border-top: 2px solid #B89F7C;}
@@ -109,11 +109,11 @@ NAV TD {
 }
 NAV INPUT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 NAV SELECT {
 	width: 100%;
-	padding: 0px;
+	padding: 0;
 }
 
 TABLE.tag_list {
