1406566 - Animations for back and forward mouse/trackpad gestures broken

Status: RESOLVED INVALID

(Firefox :: General, defect, P3)

Description

[karl.smeltzer]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:58.0) Gecko/20100101 Firefox/58.0
Build ID: 20171006100327

Steps to reproduce:

Go to about:config and set "browser.snapshots.limit" to 4 (or any positive, non-zero value).  Use mouse/trackpad gestures (2 finger swipe on MacOS) to go back or forward in history.


Actual results:

All browser contents go white and are nothing is rendered again until I restart the application.  Furthermore, the animation that does sort of play (a bar sliding across the window) is clunky and rendered at a visibly low framerate.


Expected results:

Current window contents should have animated to the side and previous (or next) page should be restored.  This is almost certainly related to the following bug, but it is set to Win32 whereas my problem occurs on MacOS.

https://bugzilla.mozilla.org/show_bug.cgi?id=1348786

Comment 1

[Milan Sreckovic [:milan] (needinfo for best results)]

Kats, is there a better component for this?  Should we have it in Widget or Panning/Zooming?

Comment 2

[Kartikaya Gupta (email:[e-mail])]

I'm not able to reproduce the problem, I used a clean profile on OS X with the latest Nightly 58.0 build. Is this only happening on specific URLs for you? I tried a few bugzilla pages (starting from this one, clicking on links here and there, and then swiping to navigate back/forward). Also, can you check to see if it happens on a clean profile? I'm wondering if you have any other changes in your profile that might be affecting this.

Comment 3

[karl.smeltzer]

Unfortunately refreshing nightly (which I think is the same as a fresh profile, right?) does not fix the problem for me, nor does disabling all extensions.  It happens on all URLs as far as I can tell (tested on Github, Bugzilla, Hacker News, etc.).  Your steps of clicking around and swiping to go back triggers this issue 100% of the time for me.  

I'm not very knowledgeable about this stuff, but could it be that it only manifests on certain graphics hardware / driver combinations?  For what it's worth this is on a 2014 MBP with only the Intel graphics chip (i.e., no discrete GPU).  I don't have any other hardware to test on.

Comment 4

[Kartikaya Gupta (email:[e-mail])]

(In reply to karl.smeltzer from comment #3)
> Unfortunately refreshing nightly (which I think is the same as a fresh
> profile, right?)

Not quite, but probably close enough. Can you also attach the contents of your about:support page?

> It happens on all URLs as far as I can tell (tested on Github,
> Bugzilla, Hacker News, etc.).  Your steps of clicking around and swiping to
> go back triggers this issue 100% of the time for me.  

Ok, thanks.

> I'm not very knowledgeable about this stuff, but could it be that it only
> manifests on certain graphics hardware / driver combinations?  For what it's
> worth this is on a 2014 MBP with only the Intel graphics chip (i.e., no
> discrete GPU).  I don't have any other hardware to test on.

It might be graphics related. It sounds like the swipe action is triggering for you, but it's just showing blank after it triggers. Just to confirm, it's only the browser content area that goes white, and the browser UI is still totally fine? Also, if you mouse over the content area, do you see the cursor change as you hover? e.g. if you hover over where there should be a link, does the cursor change to the hand pointer?

Comment 5

[karl.smeltzer]

Attachment: Raw about:support data

Comment 6

[karl.smeltzer]

(In reply to Kartikaya Gupta (email:[e-mail]) from comment #4)
> (In reply to karl.smeltzer from comment #3)
> > Unfortunately refreshing nightly (which I think is the same as a fresh
> > profile, right?)
> 
> Not quite, but probably close enough. Can you also attach the contents of
> your about:support page?

Done.

> It might be graphics related. It sounds like the swipe action is triggering
> for you, but it's just showing blank after it triggers. Just to confirm,
> it's only the browser content area that goes white, and the browser UI is
> still totally fine? Also, if you mouse over the content area, do you see the
> cursor change as you hover? e.g. if you hover over where there should be a
> link, does the cursor change to the hand pointer?

The Firefox UI is rendered fine and remains interactive and functional.  The page contents go white and moving the mouse does to where a link should be does not cause it to change.

Testing this a bit more, I noticed that while it triggers 100% of the time, I can sometimes get it to render correctly.  For example:

1. Open news.ycombinator.com and it looks fine
2. Click on top link, it looks fine
3. Swipe back.  Animation triggers but no page contents are rendered.  After the animation finishes I'm left with just a white page with no interactivity.  The URL bar shows I'm on the expected page.
4. Swipe forward.  Animation triggers again but I am not taken to the top link (from #2).  Instead it refreshes news.ycombinator.com and it renders correctly.
5. Swipe forward.  URL bar shows that I'm now back on the top link page, but contents are white again. 
6. Swipe back.  URL is still on top link and that page now refreshes and renders correctly.

If I click on the back/forward buttons I get the normal behavior.  Pressing and holding to view the page history shows only the 2 pages, not the several that I was able to swipe through.

Comment 7

[Kartikaya Gupta (email:[e-mail])]

Ok, this is sounding less like a graphics problem and more like a browser front-end issue. Particularly if the press-and-hold-back/forward to show page history isn't showing all the proper entries, it's likely some state is bad.

Comment 8

[karl.smeltzer]

(In reply to Kartikaya Gupta (email:[e-mail]) from comment #7)
> Ok, this is sounding less like a graphics problem and more like a browser
> front-end issue. Particularly if the press-and-hold-back/forward to show
> page history isn't showing all the proper entries, it's likely some state is
> bad.

Just to be clear, pressing-and-hold-back/forward looks correct.  It's only the swiping that seems to get stuck in some kind of mysterious intermediate state.

Comment 9

[Kartikaya Gupta (email:[e-mail])]

Ah, sorry, I misunderstood that part. Still, this doesn't seem like a particularly graphics-specific bug. Stephen, I think you worked on this swipe gesture at some point in the past, do you have any thoughts on where to redirect this bug?

Comment 10

[Stephen A Pohl [:spohl] (OOO until 7/30, contact :haik if urgent)]

Yes. Unfortunately, this feature is not expected to work correctly until all dependent bugs in bug 860493 are resolved. We will have to rework a lot of this feature first, including the code that is responsible for the snapshots mentioned in this bug.