Bug #10288: Fix newly identified issues to make our test suite more robust and faster
Step "Tails Greeter has applied all settings" is fragile
The test suite sometimes fails after clicking on the login button of the Greeter. The next
loginctl test to see if the X session is opened can't find one apart the Gdm one.
- 3 times so far in July
- 6 times in June
- 18 in May
- 5 in April
- 13 in March
- 12 in February
- 13 in January
But all this failures might not be due to the same reasons.
Maybe we need to raise a bit the waiting time for the session to open. Or there's a bug in the Tails X session opening, or that's #11816 having being closed a bit too fast. This needs investigation.
Test suite: drop useless code based on wrong assumptions (refs: #13470).
At least on Buster, as soon as gdm-password opens a session for the amnesia
user, a new session is registered with logind, then PostLogin is started; then,
once PostLogin has exited, LIVE_USER's gdm-x-session is started. So on Buster,
this step is almost a no-op: it will always succeed very quickly (if not on
first try) and only makes us start to wait for the desktop to be ready a tiny