Comment 35 for bug 42178

I find it very odd to see the defect I just found moving from Xubuntu 16.04 to Xubuntu 20.04.2 and Synaptic not respecting locked package versions already reported as of 2006-04-29!

Synaptic, for us, had always respected when we would put a lock on a certain package. That is no longer respected in 20.04.2.

I inquired about the trouble here:
"20.04.2 system - Will not respect Synaptic package lock at a specific version"
https://ubuntuforums.org/showthread.php?t=2464498&p=14047839

The workaround I found is:

$ sudo apt-mark hold firefox-esr-mozilla-build
$ sudo apt-mark hold firefox-mozilla-build
$ apt-mark showhold
firefox-esr-mozilla-build
firefox-mozilla-build

When I started, apt-mark did not see the lock on the two packages the Synaptic UI still recognized.

Now Synaptic no longer tries to update the packages from the versions I want maintained.

So Synaptic appears not to leverage the same flag that apt-mark is using? That seems odd and incorrect if that is the case. I would think to be dpkg compatible, Synaptic should use the same flag as other dpkg / apt tools, no?

Anyway, for us this is a definite new break moving from 16.04 to 20.4.2 versions.