Lost session

[rikona]

I use both Opera and FF, with many windows and tabs open in each.
Opera tends to get flakey [display starts to do odd things] with many
windows/tabs open, and eventually crashes with additional loading. In
the past, with Mandriva, I would switch to another user and could
again load up Opera and FF with lots of stuff in multiple users. It
was easy to switch users, so that worked well as a way of 'extending'
the browsers without problems. This is also nice since I can run the
browsers with very different privacy/security modes.

I tried this in UB - set up a new user, B, switched to it, and opened
Opera. Since this was an 'extension' of Opera, I switched back to user
A to see what I wanted to 'extend'. BUT - when I switched back to user
A, it didn't 'switch', but gave me a new login screen just as one
would have at the beginning. Since I was, at that point, unfamiliar
with switching in UB, I logged in as user A - but the original session
was gone and I lost everything that was running before the switch
[resulting in lots of cursing :-) ]. During this switch, there was a
very brief text message re changing something related to desktop, but
it went by so fast I could not read it.

I tried a test switch to/from user B, and this time I got a different
'login' screen asking for the PW for the user I was switching to,
which was NOT what I got before. At this point switching seemed to
work OK. I ran an update at this point since nothing important was
running and I could do the needed restart easily.

Two questions re the failed switch:

(1) Could the failure be caused by the fact that I had just created
user B just before the switch?

(2) Might it be because user A had the box VERY loaded - all desktops
running many apps, all memory used, and almost all swap space used too
- and it was 'too big' to switch successfully?

Any idea what that too-brief msg might have been during the failed
switch? I can't reproduce it with two lightly loaded users. Is there a
way to track it down [it was before a restart and several test
switches]?

or perhaps some reason 3?

I would like to know so this does NOT happen again - I lost a LOT of
work when the session was lost. All insights much appreciated...

Thanks,
  
 rikona