1286233 - [e10s] A second minimized window appears at Firefox startup

Status: RESOLVED DUPLICATE of bug 1211647

(Toolkit :: Startup and Profile System, defect)

Description

[Iulia Cristescu, QA [:JuliaC] (away, please needinfo? [e-mail])]

[Affected versions]:
- latest Nightly 50.0a1 (2016-07-12)
- latest Aurora 49.0a2 (2016-07-12)
- 48.0b7-build1 (20160711002726)

[Affected platforms]:
- Windows 8.1 x86
- Windows 8.1 x64

[Steps to reproduce]:
1. Launch Firefox with a new profile 
2. Inspect the Firefox icon from the Windows taskbar

[Expected result]:
- Firefox launches with one single window and no layout issues are visible

[Actual result]:
- When Firefox launches, a second window appears minimized on the taskbar for a couple of seconds; layout issues can be observed (see the screencast https://drive.google.com/file/d/0B0nYKG6PRiCcU1N6VzJTRmhESFk/view?usp=sharing)

[Regression range]:
- I will investigate for a regression range as soon as possible

[Additional notes]:
- I could not reproduce this issue on 47.0.1 build1 (20160623154057)

Comment 1

[Benjamin Smedberg]

Is this only the case for a new profile, or does it persist for multiple launches with the same profile?

Also, please test this without using the profile manager UI: using -P <profilename> in your commandline should skip the UI.

Comment 2

[Iulia Cristescu, QA [:JuliaC] (away, please needinfo? [e-mail])]

(In reply to Benjamin Smedberg  [:bsmedberg] from comment #1)
> Is this only the case for a new profile, or does it persist for multiple
> launches with the same profile?

The issue stands only for new profiles.

> Also, please test this without using the profile manager UI: using -P
> <profilename> in your commandline should skip the UI.

I've tested this way, too. The issue behaves the same way. 

In addition to these, I investigated much further and I can conclude that this is e10s related - it occurs only when e10s is enabled.

Comment 3

[Benjamin Smedberg]

Theories:
* This is a window related to onboarding, which we only show for new profiles.
* This is a window related to self-support/shield, which is supposed to run hidden at startup.

I'm not sure how to validate those: Dolske, do you know if there is a pref to disable any onboarding "stuff"? And Gregg, is there a pref to disable self-support loading?

Comment 4

[Alice0775 White]

This is by design See Bug 1156135 and .
It is not a good implementation from the point of view of the user experiences.

Comment 5

[Alice0775 White]

This is also reproduced on Nightly50.0a1 without e10s
(But the tiny browser is removed in shorter time than with e10s)

Comment 6

[Mason Chang [Inactive] [:mchang]]

Correct, you should also be seeing this without e10s, but it might be too fast to not see it.