Basically just a stripped out version of : https://github.com/Kazy/PureTabs
Tests can be run with spago test [TODO : for some reason setting npm "test" script to this value won't work]
Javascript source maps won't work out-of-the-box if JS source files are in e.g. extension/src instead of extension. This can surely be solved using this issue : https://github.com/parcel-bundler/parcel/issues/3750