1374509 - Panel jiggles / twitches sideways when opening subpanel (in overflow / page action panels)

Status: VERIFIED FIXED

(Firefox :: Toolbars and Customization, defect, P1)

Description

[Markus Stange [:mstange]]

Attachment: jank helper

Steps to reproduce:
 1. Click on the three dots button in the URL bar.
 2. Click on "Send to device...".

During the subview transition, the whole panel jiggles horizontally a little.

Sometimes it even jerks about 100px to the left for a brief time.


This effect is easier to spot if the parent process is a little janky. You can create such a janky environment artificially by opening a new non-e10s window and loading the "jank helper" attachment into it. (But remember to close that window again afterwards, because it's going to eat your battery.)

Comment 1

[:Gijs (he/him)]

Can you provide a screencast, and is this an up-to-date nightly? There were several changes in recent bugs ( bug 1370580, among other ones) that fixed this for me.

Comment 2

[Markus Stange [:mstange]]

Attachment: screen recording

This seems to still affect the 2017-06-21 nightly.

Here's a screen recording. I followed these steps:
 1. Restart nightly.
 2. Open a new non-e10s window with File -> New Non-e10s Window
 3. Load attachment 8879394 [details] in that non-e10s window.
 4. Focus an existing e10s window (this step is probably not necessary).
 4. Click the three dots button.
 5. Click Send to Device...

Comment 3

[:Gijs (he/him)]

Attachment: jerking-panel.ogg

Thanks! Converted this to ogg/theora so it works in-browser.

On the video I see 3 things. 1 is bug 1374224 - the icons load after the menu opens, which is unfortunate. More generally, because the icons don't have a size set, they cause the text to shift when they do load.

The other 2 are:
first, the panel becomes narrower because we seem to hide the main view

second, then it becomes wider again because we seem to temporarily show both the new view and the old one (which gets painted without text somehow - no idea how that is even possible, I didn't think it would be). The bizarre part is that we seem to show the new view to the left of the old one, which doesn't make a lot of sense.

Comment 5

[:Gijs (he/him)]

I think this is a side-effect from the CSS overflow properties not being set the same way as for the main hamburger panel. My patch in bug 1374315 seems to improve things. Contrary to my earlier change to the summary, I don't see any reports of this issue affecting the library panel when opened directly (ie not from within the overflow/hamburger panel), so I think it's just restricted to the page action and overflow panels which didn't/don't have a 'photon' attribute and therefore weren't getting the same overflow:hidden / overflow:visible applied to various bits of the panel, leading to some of the jumping in the screencast. 

The one thing that I'd like to double-triple-check before closing this post-1374315 is that after this is fixed, the resizing of the panel (ie there's a step in the video where the panel's current view seems to disappear) is also fixed.

Comment 6

[Mike de Boer [:mikedeboer]]

Markus, we've got a new type of animation that doesn't use a xul:stack anymore... With it, I can't reproduce the behavior. Can you?

Comment 7

[Markus Stange [:mstange]]

I can't reproduce it either. Thanks!