Where can I find the list of classes/idishshock for styling firefox through userChrome.css?

Question

Browsers

Switched to firefox, a wonderful browser, but I want to customize it for myself. There are a number of elements that I want to hide (ideally move), I came across such a wonderful userChrome.css file that allows you to do this, but I just can’t find a list of classes / IDs for each element, I have to search one by one in Google using the 'how to' method remove something in firefox', not everything is found.
Please share the list/tips (maybe there are easier ways), thanks in advance.

Answer 1

DOM Inspector + Element Inspector
Element Inspector will not work without DOM Inspector, but DOM Inspector without Element Inspector will. The second one is just for the convenience of finding elements using Shift + click on the desired element)
Only the Element Inspector has a small bug with a hotkey. Here is how to solve it.