diff --git a/core/manipulate-dom.js b/core/manipulate-dom.js
index 1d7d2382..d972653c 100644
--- a/core/manipulate-dom.js
+++ b/core/manipulate-dom.js
@@ -88,9 +88,17 @@ manipulateDOM._removeCrossOriginAndIntegrityAttr = function (details) {
 
                             htmlHead = asciiDecoder.decode(evt.data, {'stream': false});
                             // eslint-disable-next-line no-useless-escape
-                            charsetMatch = htmlHead.match(/<meta.*charset=["']?([^>"'\/]+)["'].*[>\/]/i);
+                            charsetMatch = htmlHead.match(/<meta\s+charset=["']?([^>"'\/]+)["'>\/]/i);
+                            if (charsetMatch === null) {
+                                // eslint-disable-next-line no-useless-escape
+                                charsetMatch = htmlHead.match(/<meta.*charset=["']?([^>"'\/]+)["'].*[>\/]/i);
+                            }
 
-                            charset = charsetMatch ? charsetMatch[1] : 'UTF-8';
+                            if (EncodingTypes[charsetMatch[1].toLowerCase()] !== undefined) {
+                                charset = charsetMatch[1];
+                            } else {
+                                charset = 'UTF-8';
+                            }
                         }
                         decoder = new TextDecoder(charset);
                     }
diff --git a/pages/updates/updates.html b/pages/updates/updates.html
index a7bb98ae..3b979686 100644
--- a/pages/updates/updates.html
+++ b/pages/updates/updates.html
@@ -40,6 +40,7 @@
                         <li>Updated: Vue v3.0.5 -> v3.0.6 (<a href="https://codeberg.org/nobody/LocalCDN/issues/290">#290</a>)</li>
                         <li>Added: vue-i18n v9.0.0 (<a href="https://codeberg.org/nobody/LocalCDN/issues/291">#291</a>)</li>
                         <li>Updated: angular.js v1.7.9 -> v1.8.2 (<a href="https://codeberg.org/nobody/LocalCDN/issues/292">#292</a>)</li>
+                        <li>Fixed: Charset detection in HTML filter improved and check if supported (<a href="https://codeberg.org/nobody/LocalCDN/issues/293">#293</a>)</li>
                     </ul>
                     <div id="generator-section">
                         <div class="topic-label">