If GPG key validation fails, check the key name

[lproven]

This is a continuation of the issue I reported at:
BrowserWorks/Waterfox#2786

I have traced the issue, and it is not an obvious one, so I thought I should share the fix. It took me months and in the interim I had to use an AppImage of Waterfox because I could not install new versions from the repo.

Deleting and re-adding the PPA did not help. Fetching a new key did not help.

The issue is caused by a change of the filename in which the GPG key is kept.

The key is now called: home_hawkeye116477_waterfox.gpg

It is kept in /etc/apt/trusted.gpg.d, which is a folder I have never entered before.

It does not help to remove the key, as I was advised in the previous bug report. The problem is that the filename used to be called home:hawkeye116477_waterfox.gpg and apt still reads that key first.

So it makes no difference how many times you remove or refresh home_hawkeye116477_waterfox.gpg so long as the older key with a colon instead of the first underscore is still present.

Only when home:hawkeye116477_waterfox.gpg is removed does apt use home_hawkeye116477_waterfox.gpg instead. After this, apt update runs fine, without error, and newer versions can be installed. Mine went straight from Waterfox 4 to version 5.1 once I discovered this.