1687823 - [Bug] White screen displayed when minimizing Suggested logins menu on Android

Status: NEW

(Core :: Graphics, defect, P2)

Description

[Amedyne Moya [:amoya]]

From github: https://github.com/mozilla-mobile/fenix/issues/17170.

Steps to reproduce

1. Access accounts.google.com.
2. Tap on the arrow in order to expand the Suggested logins menu.
3. Minimize the Suggested logins menu.

Expected behavior

The accounts.google.com webpage is correctly displayed.

Actual behavior

White screen displayed when minimizing Suggested logins menu

Device information

• Android device: Google Pixel 4 XL (11).
• Fenix version: Nightly 21/12.

Note that I had to refresh the page by scrolling down in order to see the webpage.

Change performed by the Move to Bugzilla add-on.

Comment 1

[Emily Toop (:fluffyemily)]

Needs investigating to determine whether this is GV or graphics.

Comment 2

[[ex-Mozilla] Agi Sferro | :agi]

Attachment: Bug 1687823 - Add menu item to collapse the GV view.

Comment 3

[[ex-Mozilla] Agi Sferro | :agi]

Attachment: Bug 1687823 - Remove dead code in GeckoScreenOrientation.

Comment 4

[[ex-Mozilla] Agi Sferro | :agi]

I can reproduce in GVE by setting the view height to 0. I can see we're calling child->ResumeAndResize(aX, aY, aWidth, aHeight); with the correct values here: https://searchfox.org/mozilla-central/rev/3ff133d19f87da2ba01ade55d6e7fdf0fc28b08c/widget/android/nsWindow.cpp#1127

And that we're getting called back in here: https://searchfox.org/mozilla-central/rev/3ff133d19f87da2ba01ade55d6e7fdf0fc28b08c/widget/android/nsWindow.cpp#1171

so this looks like a graphics problem to me.

To reproduce:

• Apply patch from Bug 1692246
• navigate to https://accounts.google.com/signin/v2/identifier?flowName=GlifWebSignIn&flowEntry=ServiceLogin
• click on three dots -> collapse (this makes the surface size 0x0)
• wait a few seconds
• click on collapse again (this restores the surface size back)

at this point you will see a white screen, tapping on the screen (e.g. by trying to scroll) makes the content appear. I can only reproduce this sometimes, so maybe try a few times if you can't reproduce. I could reproduce both on the emulator and on my S10.

Comment 5

[Phabricator Automation]

Comment on attachment 9202618 [details]
Bug 1687823 - Add menu item to collapse the GV view.

Revision D104842 was moved to bug 1692246. Setting attachment 9202618 [details] to obsolete.

Comment 6

[Phabricator Automation]

Comment on attachment 9202619 [details]
Bug 1687823 - Remove dead code in GeckoScreenOrientation.

Revision D104843 was moved to bug 1692246. Setting attachment 9202619 [details] to obsolete.

Comment 7

[Chris Peterson [:cpeterson]]

Tagging as [geckoview:2022h2] because csadilek thinks this bug is worth investigating.

Comment 8

[Jamie Nicol [:jnicol]]

Just an update, as I am investigating this. It seems to reproduce on any page which will continue painting in the background, for example due to the blinking cursor on the login page. It also reproduces by highlighting the search bar on google.com.

So with the cursor blinking, after collapsing the GeckoView we continue painting, but most of the items in the display list now have a clip with a very negative height (so do not get rendered, as expected). Uncollapsing the GeckoView, however, does not restore this clip to a positive size, even if the cursor is still blinking. But interacting with the page in another way forces a paint which does have the correct clips.

I'll continue investigating where this clip comes from, and where it should be being restored to a positive value. (It's unfortunately just a slow process working backwards through this code I haven't been familiar with for years. I really wish we had rr on android!!)