Перевел кномки управления на domnodeinserted

controls.css

@@ -43,7 +43,7 @@
     position: relative; 
     display: inline-block;
     vertical-align: top;
-    background: url('chrome-extension://__MSG_@@extension_id__/mute.png') no-repeat top left;
+    /*background: url('chrome-extension://__MSG_@@extension_id__/mute.png') !important;*/
     background-repeat: no-repeat;
     padding: 6px;
 }

controls.js

@@ -30,8 +30,7 @@ showMembersBtn.addEventListener('click', function() {
 */
 
 function muteBtnHTML(id) {
-    return `
-    <span class="mute_message" id="mute` + id + `">
+    return `<span class="mute_message" id="mute` + id + `">
         🔇
         <span class="mutetooltip">Заглушить</span>
     </span>`
@@ -42,6 +41,7 @@ function addControls() {
 
     for (var item of messages) {
         var actionsArea = item.getElementsByClassName("im-mess--actions")[0];
+        if (actionsArea && actionsArea.lastChild.className != "mute_message") {
             var sender_id = item.parentElement.parentElement.parentElement["dataset"].peer
 
             actionsArea.innerHTML += muteBtnHTML(sender_id);
@@ -49,7 +49,7 @@ function addControls() {
             muteBtn.style.display = "none";
 
             actionsArea.parentElement.addEventListener("mouseenter", function( event ) {
-            event.target.getElementsByClassName("mute_message")[0].style.display = "";
+                event.target.getElementsByClassName("mute_message")[0].style.display = "inline-block";
             });
 
             actionsArea.parentElement.addEventListener("mouseleave", function( event ) { 
@@ -65,6 +65,13 @@ function addControls() {
                 });
             });
         }
+    }
 }
 
-addControls();
+var chatBody = document.getElementsByClassName("_im_peer_history im-page-chat-contain")[0];
+
+chatBody.addEventListener('DOMNodeInserted', function(event) {
+    if (event.target.className == 'im-mess--check fl_l') {
+        addControls();
+    }
+});

manifest.json

@@ -24,7 +24,7 @@
       "js": ["hide_element.js"]
     },
     {
-      "matches": ["https://*.vk.com/*"],
+      "matches": ["https://*.vk.com/im*"],
       "js": ["controls.js"],
       "css": ["controls.css"]
     }