1295123 - Middle click does not register intermittently

Status: UNCONFIRMED

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

Description

[6lobe]

Middle clicking on a link/button/UI element sometimes does not register. 

This is especially noticeable if you use the middle mouse button to manage tabs during browsing.

Often when middle clicking the tab strip to open a new tab or clicking on an existing tab to close it, nothing happens and you need several clicks for the action to register and suddenly, you have accidentally opened/closed multiple tabs.

This is also noticeable if you open several links on a web page in succession with the middle mouse button.

For example here: https://news.ycombinator.com/

Also sometimes when middle clicking a link Firefox erroneously starts to autoscroll instead of opening the link you middle clicked.

I set the platform to Linux since I am on Linux currently and cannot test this on Windows at the moment, but I do have the recollection that this issue is also present on Windows and all versions of Firefox. Maybe it just is more noticeable on my current platform, if it makes any difference I am using an older Core 2 Duo as my CPU.

Comment 1

[Hsin-Yi Tsai (she/her) [:hsinyi]]

I don't have problems with opening or closing multiple tabs. Old CPU could be suspicious...

Hi Stone, how much do you think it's related to the old hardware? Could you help confirm the issue? Thanks.

Comment 2

[Hsin-Yi Tsai (she/her) [:hsinyi]]

(In reply to Hsin-Yi Tsai [:hsinyi] from comment #1)
> I don't have problems with opening or closing multiple tabs. Old CPU could
> be suspicious...
> 
> Hi Stone, how much do you think it's related to the old hardware? Could you
> help confirm the issue? Thanks.

b.t. w. there's another bug 1240704 might be related?

Comment 3

[Ming-Chou Shih [:stone]]

I have no idea about this bug. I tried some tools like cpulimit / taskset to limit the CPU usages, sometimes I can reproduce the slow responses time problem of middle click. But it's hard to say it's because the  hardware. I need more hints to carry on it.

Comment 4

[Hsin-Yi Tsai (she/her) [:hsinyi]]

(In reply to Ming-Chou Shih [:stone] from comment #3)
> I have no idea about this bug. I tried some tools like cpulimit / taskset to
> limit the CPU usages, sometimes I can reproduce the slow responses time
> problem of middle click. But it's hard to say it's because the  hardware. I
> need more hints to carry on it.

Yes... understood that we do need more profiling data before being able to figure out the root cause. Let's see if we could come up with some ideas helping clarifying this issue first!

Before the root cause is confirmed, it's hard to say the priority, so using P3 + "perf" keyword for tracking this kinda issue.

Comment 5

[Hsin-Yi Tsai (she/her) [:hsinyi]]

(In reply to Ming-Chou Shih [:stone] from comment #3)
> I have no idea about this bug. I tried some tools like cpulimit / taskset to
> limit the CPU usages, sometimes I can reproduce the slow responses time
> problem of middle click. But it's hard to say it's because the  hardware. I
> need more hints to carry on it.

Hi Olli, maybe you could shed some light here?

Comment 6

[6lobe]

This mainly happens when there is activity/load. For example background tab loading/activity.

I can always reproduce by opening links in succession at https://news.ycombinator.com/

I feel this is now a bit better during light browsing but still an issue.

Interestingly I dont get this issue when interacting with the bookmarks sidebar.