Looks like safari

without trans;usent effect with translusent effect

Steps for applying this configuration:

Type about:profiles into your urlbar and go to the page
Open the root directory folder specified on the page
Inside this folder, create a folder named "chrome"
Put the userchrome.css file from this repo into the chrome folder
Type about:config into your urlbar and go to the page
Paste "toolkit.legacyUserProfileCustomizations.stylesheets" into the bar and set its value to true
Go back to about:profiles and click the restart normally buton
That should be it!

You may how to adjust some parameters as they are adjusted to my resolution