#allow add search engine
  browser.urlbar.update2.engineAliasRefresh true
  
  browser.urlbar.trimURLs false
  
  full-screen-api.transition-duration.leave 0 0
  full-screen-api.transition-duration.enter 0 0
  
  #enable loading indicator from hourglass to animation
  ui.prefersReducedMotion 0
  
  #enable compact mode
  browser.compactmode.show true
  
  #fingerprint resistence
  privacy.resistFingerprinting false
  privacy.fingerprintingProtection true
  privacy.fingerprintingProtection.overrides +AllTargets,-FontVisibilityBaseSystem,-FontVisibilityLangPack
   
adjust tab bar height:

  about:config -> toolkit.legacyUserProfileCustomizations.stylesheets -> true
  about:support -> Open folder
  create chrome/userChrome.css

add following content to chrome/userChrome.css:

<code>
/* Reduce tab height */
#TabsToolbar {
  --tab-min-height: 25px !important; /* Default is ~36px, adjust as needed */
}

.tab-content {
  padding-block: 2px !important;
}
</code>