Fix Firefox mute icon to not expand tab, moved left and behave like before v136 version

userChrome.css

/* Setup userChrome.css using https://www.userchrome.org/how-create-userchrome-css.html and add this content into the file */
/* This will make the mute button behave like it was before v136 by positioning mute button to the left of the tab instead of the site favicon and not expanding the tab */

.tabbrowser-tab:is([muted], [soundplaying], [activemedia-blocked]) {
  #tabbrowser-tabs[orient="horizontal"] &:not([pinned]) {
    --tab-min-width: inherit !important;
    --tab-min-width-pref: inherit !important;
    min-width: max(var(--tab-min-width-pref, var(--tab-min-width))) !important;
  }
}

.tab-audio-button {
  position: absolute !important;
  left: 4px !important; 
  top: 50% !important;
  transform: translateY(-50%) !important;
  z-index: 2 !important; 
  margin: -5 !important;
  padding: 0 !important;
  font-size: 18px !important;
}

.tabbrowser-tab[soundplaying] .tab-icon-image {
  visibility: hidden !important;
}