This really needs to be a default option Mozilla!!! Put the Firefox Findbar (Ctrl-F) search back to the top where it belongs!

Pre Firefox v155+ updates will likely leave your userChrome custom CSS destroyed and parts of your Firefox UI missing or semi-broken. Awesome work by user "AluminumFoyle" on Reddit who posted this solution for your userChrome profile: https://redlib.privacyredirect.com/r/FirefoxCSS/comments/1w50dgs/firefox_version_155_broke_an_old_userchromecss_i/p7bpnev/?context=3#p7bpnev.

This code below will also increase your pinned tab width for a little bit more context.

/* Force findbar back to the top in Firefox 155+ */
.browserContainer {
  display: flex !important;
  flex-direction: column !important;
}
.browserContainer > .browserStack {
  order: 2 !important;
  flex: 1 1 auto !important;
}
.browserContainer > findbar {
  order: 1 !important;
  border-top: none !important;
}

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */

.tab-label-container[pinned]{
  width: 60px !important;
}