1257453 - Restoring into existing tab with mismatch userContextId should create a new tab

Status: RESOLVED DUPLICATE of bug 1274461

(Firefox :: Session Restore, defect, P2)

Description

[Yoshi Cheng-Hao Huang [:allstars.chh][:allstarschh][:yoshi]]

See ttaubert's and sicking's comments in 
https://bugzilla.mozilla.org/show_bug.cgi?id=1250063#c38
https://bugzilla.mozilla.org/show_bug.cgi?id=1250063#c42

Comment 1

[Yoshi Cheng-Hao Huang [:allstars.chh][:allstarschh][:yoshi]]

Hi Tanvi
Do you have more reasons to make this P1?
From https://bugzilla.mozilla.org/show_bug.cgi?id=1245502#c9 I thought session restore is not in priority, also that bug is P2.

And this bug is 'restore into an *existing* tab', which makes the use case is less than regular restore.
From Jonas' comment from Comment 0, I think he doesn't know we restore into existing tabs, which I think the use case for this bug is pretty rare.

Comment 2

[Tanvi Vyas[:tanvi]]

Spoke to Yoshi about why this is a P1.  We want to ensure that we don't change ever change the usercontextId on an existing tab.

Comment 3

[Tanvi Vyas[:tanvi]]

Making this a P2 to be done in June for Nightly 50.

Comment 4

[Yoshi Cheng-Hao Huang [:allstars.chh][:allstarschh][:yoshi]]

When working on Bug 1274461 I found that it will have the case that existing tab has different userContextId, for example, in about:home, there's a  'restore last session' button. If we have container tab in the previous session, then when 'Restore Last Session' is pressed, the about:home tab will be used to restore the first container tab.

So I'll duplicate this.