Extension to Toggle Pinned Tabs in firefox via a keybind
In Zen Browser or Firefox, go to about:addons. Click the settings gear next to Manage Your Extensions, and select Install Add-on from File.
Choose the built zip file. And allow unsigned addons
Used in Zen browser. Another item that is useful in Zen, is to disable the default command for Bookmarking a tab. Once this is done, and the addon is installed, this will mimic Arc browsers Pin Tab command
In manifest.json update the keybind to whatever you would like. Then run pnpx web-ext build --overwrite-dest to build out a new extension package to be installed.
Do as you please.