Are you using noscript or a similar addon, possibly uMatrix, that blocks javascript, cookies and third party requests? If so (and probably even if you don't) then you have seen web pages become virtually unreadable for all the additional nagging elelments that pop up top, bottom, left and right.

I finally manned up to tackle the ghacks (now arkenfox on github) user.js for Firefox. I felt that if I want to continue using Firefox I really have to do this, since it's making more and more unbidden connections. Thankfully it is possible to disable most.

At some point Firefox developers "simplified" the Advanced Configuration Editor a.k.a. about:config - one cannot even sort by columns anymore! Which makes it extremely tedious to hunt down user modified settings. Fortunately, the previous, more useful editor is still available at chrome://global/content/config.xhtml:

I decided to use Firefox ESR (currently 78) instead of the faster moving Firefox release favoured by Archlinux (currently 81). Upon first starting Firefox ESR, it does not accept the default profile but creates a new one instead, and I cannot force it to use my old profile with all its bookmarks, addon configurations etc.

This cost me several hours of my life, so I'm putting it here never to be forgotten: Source

It seems I had to make the switch away from seamonkey. Firefox for now, but I will consider palemoon again. Anyhow, revisiting my browsing & addon habits, I re-discovered this thread and the uMatrix addon - I am amazed! It can replace NoScript, my beloved but unavailable RequestPolicy, a Cookie blocker, and an adblocker (maybe more).

What if your Mozilla-browser's favourite theme lacks nice folder icons? You don't have to rewrite the theme, it's enough to create or edit your profile-folder/chrome/userChrome.css e.g. like this: Remember that the folder path still starts with a slash '/', so you end up having three slashes: