I run two Mint machines, 19.3 and 20, both have Firefox set to auto update.
My Mint 19.3 Firefox updates automatically, but my Mint 20 install doesn't. Couldn't find anything on the Mint site, maybe someone here can offer a tip or two.
Here's the tech bit:
Code:
Mint 19.3 - Firefox version is 82.0.6 64bit
about:config - app.update.auto is true
Mint 20 - Firefox version is 79.0 64bit
about:config - app.update.auto is true
cheers folks