1726307 - Clicks propagating behind context menu while using graphics tablet.

Status: RESOLVED FIXED

(Core :: DOM: UI Events & Focus Handling, defect, P3)

Description

[bin.sayantan]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0
Firefox for Android

Steps to reproduce:

I am using a Huion tablet (HS64).
I believe this will also happen on any touchscreen based pen device.

1. Long press on a web page item (links,etc..) to open the context menu using the pen. OR use the pen to open the browser hamburger menu on top right.
2. Click on a context menu item using the pen.

Actual results:

The menu item gets clicked but also anything on the web page behind the menu item gets clicked. Any link, button, image right behind the spot where the pen was used to select the menu item, gets clicked.

This even affects Firefox items. Say the context menu got laid above the tabs area, clicking on the topmost item with the pen changes the tab which was just behind the menu option.

Expected results:

Only the context menu item should get clicked. Not the web page elements behind the conetxt menu.

I have tried to reproduce this on Microsoft Edge, and this does not happen there. So its not a driver related issue. I have also tried it on incognito mode with all extensions disabled, and it still occurs, hence it is not an extension issue.

Comment 1

[bin.sayantan]

I do not know why it got labelled as "Firefox for Android", but it is occurring on desktop.
Firefox 91 stable.
Build: 20210804193234
OS: Windows 10.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Firefox::Menus' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Comment 3

[Kagami Rosylight [:saschanaz] (they/them)]

Hi reporter, could you try Firefox Nightly (https://nightly.mozilla.org) and see it still happens?

I suspect somehow the pen input happens more than once by a single pen contact, but it's not reproducible on Surface Pro 7.

Comment 4

[bin.sayantan]

Hi Kagami.
So I tried out the Firefox nightly version 93a1.
The issue is even worse there. I cannot even click on any context menu option using the pen.
At-last on the current stable version I can click the menu items, that's not happening on nightly.

Firefox Nightly version:
Version : 93.0a1
Build ID : 20210824215948

Comment 5

[Olli Pettay [:smaug][[e-mail]]]

[Tracking Requested - why for this release]:
Sounds like something has regressed to make the behavior even worse.

Comment 6

[Julien Cristau [:jcristau]]

Sounds like there's 2 issues, the behaviour in 91 (which may or may not be a regression, and is P3/S3 as per :saschanaz), and in 93 (which is worse, and probably more urgent unless it's behind a nightly-only pref?). Which do we want to track here?

Comment 7

[bin.sayantan]

I do not know how FF is developed, but my basic logic says you guys may have already done some work on pen support from 91 to 93. So creating patch separately for 91 is kinda useless. If the issue can be fixed on 93 (nightly) then it might solve this issue in this bug report as well.

Comment 8

[Kagami Rosylight [:saschanaz] (they/them)]

The currently Nightly-only dom.w3c_pointer_events.dispatch_by_pointer_messages is causing the Nightly menu issue, tracking in bug 1727722.

Comment 9

[bin.sayantan]

Can confirm.
Disabling that flag dom.w3c_pointer_events.dispatch_by_pointer_messages does make the context menus clickable again with the pen in 93 (nightly).
After that the behaviour is identical to what is mentioned in this bug report.

Comment 10

[Julien Cristau [:jcristau]]

Thanks.

Comment 11

[Kagami Rosylight [:saschanaz] (they/them)]

Could you try again on today's Nightly and check it still happens?

Comment 12

[bin.sayantan]

Hi Kagami.
Issue is not resolved.
Exactly same behavior as before.
Need to disable that flag to make click using pen.
After disabling, still click-through occurs.

Version 93.0a1
Build ID 20210830162701

Comment 13

[Kagami Rosylight [:saschanaz] (they/them)]

Could you check update and get 2021-08-31 build (or newer)? 2021-08-30 didn't include the fix for bug 1727722.

My expectation is that it should be clickable but the click-through will probably still happen.

Comment 14

[bin.sayantan]

Hi Kagami.
Looks like the issue is completely fixed in 2021-08-31 build.

Clicking using pen works without changing the flag dom.w3c_pointer_events.dispatch_by_pointer_messages.
Click-through is not happening. Yayyy! Clicking the context menu options no longer click items on the web page!

Disabling the flag dom.w3c_pointer_events.dispatch_by_pointer_messages makes click-through context menu bug to reappear.

So I guess the issue is resolved now.

Version 93.0a1
Build ID 20210831213957

Comment 15

[Kagami Rosylight [:saschanaz] (they/them)]

Hooray, thank you for confirming 👍

Will keep this until the flag reaches stable builds.

Comment 16

[bin.sayantan]

Cool! Thank you so much.
Great job FF team.

Comment 17

[BugBot [:suhaib / :marco/ :calixte]]

The bug has a release status flag that shows some version of Firefox is affected, thus it will be considered confirmed.

Comment 18

[Julien Cristau [:jcristau]]

Closing per comment 14.