Fix: use correct selector #contact-widget-auto to hide Knocket widget

layout/includes/third-party/chat/knocket.pug

@@ -8,22 +8,33 @@ script.
       const isChatBtn = !{theme.chat.rightside_button}
       const isChatHideShow = !{theme.chat.button_hide_show}
 
-      const getWidget = () => document.querySelector('#knocket-widget, [id*="knocket"]')
+      const getWidget = () => document.getElementById('contact-widget-auto')
 
       if (isChatBtn) {
         const hide = () => { const w = getWidget(); if (w) w.style.display = 'none' }
         const show = () => { const w = getWidget(); if (w) w.style.display = '' }
 
+        // Hide the native Knocket floating button
+        const observer = new MutationObserver(() => {
+          if (getWidget()) { hide(); observer.disconnect() }
+        })
+        observer.observe(document.body, { childList: true, subtree: true })
         hide()
 
         window.chatBtnFn = () => {
           const w = getWidget()
-          if (w && w.style.display === 'none') show()
+          if (!w) return
+          if (w.style.display === 'none') show()
           else hide()
         }
 
         document.getElementById('chat-btn').style.display = 'block'
       } else if (isChatHideShow) {
+        const observer = new MutationObserver(() => {
+          if (getWidget()) observer.disconnect()
+        })
+        observer.observe(document.body, { childList: true, subtree: true })
+
         window.chatBtn = {
           hide: () => { const w = getWidget(); if (w) w.style.display = 'none' },
           show: () => { const w = getWidget(); if (w) w.style.display = '' }