A while ago I found out about the firefox addon stylish. It’s an addon that allows you to change the look of your browser and specific websites. Unlike themes it can completely redecorate almost all elements like the url bar, bookmark bar etc.
A small side note: The addon has sadly been bought by a big company. This is not the first time this has happened to an addon, but sadly this means using the addon will send information to that company, since that’s pretty much the only reason they bought it. Currently this is only enabled in chrome and can be disabled under the settings. An update for firefox will probably follow at some point, but I doubt that the option to disable the information collection is here to stay. So use this addon only if you’re okay with sharing some of your data (which I am not). There’s an alternative for chrome called StyleRRR (Chrome/Firefox).
On userstyles.org you can browse website and browser styles. I for one installed DarkTube so the YouTube design is easier on the eyes. So yeah with stylish you can have dark themes for most popular websites which don’t natively support it.
So since only making YouTube darker is kinda lame i also wanted firefox to be more darkish and more flat. So after some searching I came across powerline. Which is pretty cool, but the theme doesn’t include the bookmark bar nor the addon icons. But with my amazing css skills and some googling I modified powerline to fit my needs.
So as you can see Firefox is now entirely dark themed. The tabs look a little bit like those from chrome and they take up 100% of the window width, devided evenly to all open tabs. The url is centered at the top and on right are the icons from my addons. It’s not perfect but it does the trick.
So if you want to try my version you can get it here. Just copy the css text, make a new style under about:addons and paste in the text.