This repo is unmaintained and has been archived. Now you can enable overlay scrollbars in Firefox by adding ui.useOverlayScrollbars with value of 1 in about:config. Firefox GNOME theme has this config enabled by default.
Here you can find a Firefox script providing GNOME overlay scrollbars previously included in the Firefox GNOME theme.
git clone https://github.com/rafaelmardojai/firefox-gnome-scrollbars.git && cd firefox-gnome-scrollbars
./install.sh-
Copy
user_chromecontents (gnome-scrollbars.uc.jsfile &utilsfolder) to your Firefox profile chrome folder (FIREFOX_PROFILE\chrome). -
Copy
firefox_installcontents (config.jsfile anddefaultsfolder) to Firefox installation folder, usually found in/usr/lib/firefoxor/usr/lib64/firefox.
This project includes a custom JS scripts loader based on firefox-scripts by xiaoxiaoflood, so any
.uc.jsfile put inFIREFOX_PROFILE\chromewill be loaded.
If you already use some custom JS scripts loader, just copy
user_chrome/gnome-scrollbars.uc.jsfile.
Sometimes after changes you should remove your Firefox profile cache folder to get things working, found in ~/.cache/mozilla/firefox/.