In firefox you come on websites like youtube where you need to type in your name or a description and the inputbox is nearly unreadable.

The fact that it is unreadable might be due to the settings of the dark theme you are using. I am using the Arc theme from horst3180 and this is the fix.

We download from this github

and run one script to fix the issue in the folder personal. Mind you. First startup firefox then run the script.