I have answered what I think is a similar question here. I have copy-pasted most of the answer from there below. I don't know if it is ethical to do. Apologies in advance if it isn't. If it isn't the right thing to do , I'll delete it.
The following deals with Firefox, but the relevant code should be usable in Google Chrome when placed in ~/.config/google-chrome/Default/User Stylesheets/Custom.css
. For Chromium, look in ~/.config/chromium/Default/User StyleSheets/
. I have no knowledge about the third browser.
Close (exit) all instances of Firefox.
Go to your profile folder. It is here: /home/your_name/.mozilla/firefox/randomstring.default
. In there, look for a subfolder called chrome
.
If it doesn't exist, create it.
To create the chrome
folder you can use your file manager (or the command line with mkdir chrome
).
If chrome
does exist, look for a file called userContent.css
. Otherwise, create an empty text file with this name in the chrome
folder.
Now open userContent.css
with a text editor and paste in or append this code:
INPUT, TEXTAREA {color: black !important; background: #aaaaaa !important; }
Save the file (as plain text) and close the text editor.
Restart Firefox.
You should now have black text on a light gray background. You can use whatever color combination you prefer.
Notes: chrome
and userContent.css
are case-sensitive and should be spelled correctly. The settings here will take precedence over those in the OS theme and will remain the same in Firefox irrespective of which gtk
theme you switch to.