Utility tools to handle ungoogled-chromium installation

General system assumptions:

• packages are extracted in /opt/, e.g. /opt/ungoogled-chromium_107.0.5304.68-1.1_linux ;
• a symlink /opt/ungoogled-chromium points to the folder of the current version ;
• a symlink /opt/bin/ungoogled-chromium points to the currently used version's folder chrome-wrapper through /opt/ungoogled-chromium.

/opt/bin/ungoogled-chromium -> /opt/ungoogled-chromium/chrome-wrapper
/opt/ungoogled-chromium     -> /opt/ungoogled-chromium_XXX.X.X_linux/

update.sh: install and "update" ungoogled-chromium (portable builds)

Inputs (provided or asked by script):

• package URL ;
• package sha256 checksum ;

found here.

Script downloads package, computes and verifies checksum, extracts package to /opt (can be overridden by provided argument), copies Widevine installation from same major version if found or asks to install it (using widevine.sh).

widevine.sh: install Widevine for ungoogled-chromium from Google Chrome

Based on script by dkebler.

I've modified the script so that it looks for the "compatible" version – i.e. same major digit – in Google's repo Packages file instead of trying to download the exact same version as ungoogled-chromium's version – which repeatedly failed with the versions I was using with the original script.