diff --git a/extension/content-script.js b/extension/content-script.js
--- a/extension/content-script.js
+++ b/extension/content-script.js
@@ -814,27 +814,36 @@
             player.addEventListener("pause", player.replayAfterRemoval);
         `;
 
-        executeScript(`function() {
+        const handleCreateElement = `
+            const tagName = arguments[0];
+            if (typeof tagName === "string") {
+                if (tagName.toLowerCase() === "audio") {
+                    const player = createdTag;
+                    ${addPlayerToDomEvadingAutoPlayBlocking}
+                } else if (tagName.toLowerCase() === "video") {
+                    (document.head || document.documentElement).appendChild(createdTag);
+                    createdTag.parentNode.removeChild(createdTag);
+                }
+            }
+        `;
+
+        if (IS_FIREFOX) {
+            var oldCreateElement = Document.prototype.createElement;
+            exportFunction(function() {
+                const createdTag = oldCreateElement.apply(this, arguments);
+                eval(handleCreateElement);
+                return createdTag;
+            }, document, {defineAs: "createElement"});
+        } else {
+            executeScript(`function() {
                 var oldCreateElement = Document.prototype.createElement;
                 Document.prototype.createElement = function() {
-                    var createdTag = oldCreateElement.apply(this, arguments);
-
-                    var tagName = arguments[0];
-
-                    if (typeof tagName === "string") {
-                        if (tagName.toLowerCase() === "audio") {
-                            const player = createdTag;
-                            ${addPlayerToDomEvadingAutoPlayBlocking}
-                        } else if (tagName.toLowerCase() === "video") {
-                            (document.head || document.documentElement).appendChild(createdTag);
-                            createdTag.parentNode.removeChild(createdTag);
-                        }
-                    }
-
+                    const createdTag = oldCreateElement.apply(this, arguments);
+                    ${handleCreateElement}
                     return createdTag;
                 };
-            }
-        `);
+            `);
+        }
 
         // We also briefly add items created as new Audio() to the DOM so we can control it
         // similar to the document.createElement hack above since we cannot share variables