Fix code-charity#2069: Transparent top bar stops working when scroll.

This commit resolves issue code-charity#2069, where the transparent top bar would lose its transparency effect upon scrolling. The issue was addressed by removing unnecessary icons and adjusting opacity settings to maintain the desired transparent appearance even during scrolling. It also have modifications that admin requested to. Removed not necessary lines.

js&css/web-accessible/www.youtube.com/appearance.js

@@ -615,16 +615,4 @@ if (ImprovedTube.storage.header_transparent === true) {
             document.documentElement.removeAttribute('data-scroll-direction');
         }
     });
-
-    /*------------------------------------------------------------------------------
-    SHOW/HIDE VOICE SEARCH BUTTON
-    ------------------------------------------------------------------------------*/
-    window.addEventListener('scroll', function() {
-        var voiceSearchButton = document.getElementById('voice-search-button');
-        if (window.scrollY === 0) {
-            voiceSearchButton.style.display = 'block';
-        } else {
-            voiceSearchButton.style.display = 'none';
-        }
-    });
 }