Comment 7 for bug 1567194

Pasting the important bits from some private email conversation here, for posterity.

My reply:
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At the moment we told the boot sequence these two:

 * ubiquity runs before stopping plymouth since
   http://bazaar.launchpad.net/~ubuntu-installer/ubiquity/trunk/revision/6363

 * We must start gettys after stopping plymouth as otherwise they
   would disrupt the plymouth VT.

Thus transitively we said "run ubiquity before gettys". If we want to
stop doing that, we must either drop one of these two, or pin plymouth
to VT7 (not sure where it's running ATM, but this would mean even more
VT switches, increasing the flicker) or stop using plymouth for
ubiquity-only mode. The latter might be an option?

We haven't really discussed this bug after the 16.04 release week, as
it seems fairly low-priority: if you want to do other things while the
installing, just start the live desktop session and run ubiquity from
there.
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Mathieu's reply:

TBH, I think the second solution is probably best (along with making sure
plymouth runs on the right VT, which is likely 7). This would allow us to
bring up the gettys in background and have them ready when plymouth finally
quits, as you can sometimes run into a blank VT for server installs with no
getty appearing -- I'm thinking this might actually be fixed by such a
change as well.