Might be duplicate of https://bugs.chromium.org/p/chromium/issues/detail?id=778992

Stefan, could you please help triage this bug ?

This is reproducible on linux with the #overlay-scrollbars flag enabled.

Off the top of my head, my theory is that the hit test is getting clipped to the bounds of the height:1px div that actually owns the scrollbar.

Are there any updates to this bug which I can provide to customer?

I have a fix in progress, but it's unlikely to land until the first week of January.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b541aa7c439e96b9c00ce6a70d7baa4fa8f17b48

commit b541aa7c439e96b9c00ce6a70d7baa4fa8f17b48
Author: Stefan Zager <szager@chromium.org>
Date: Fri Jan 05 22:45:29 2018

Fix hit testing overlay scrollbars

The previous code computed the wrong y-coordinate for the top of the
horizontal scrollbar.

Bug:  782802 
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
Change-Id: Ic31f94ca2a3e45881682940ae28f754894159a51
Reviewed-on: https://chromium-review.googlesource.com/843777
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Commit-Queue: Stefan Zager <szager@chromium.org>
Cr-Commit-Position: refs/heads/master@{#527415}
[modify] https://crrev.com/b541aa7c439e96b9c00ce6a70d7baa4fa8f17b48/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp
[modify] https://crrev.com/b541aa7c439e96b9c00ce6a70d7baa4fa8f17b48/third_party/WebKit/Source/core/paint/PaintLayerScrollableAreaTest.cpp

Can we confirm if the fix has landed? 

it's in canary:
Commit b541aa7c... initially landed in 65.0.3313.0

We are still seeing the same issue even with the latest version of Canary.  Here is a link with a video of the behavior.

https://drive.google.com/file/d/1zPuKIrrcuVxSYfcbGX226Bdjvne-V3JB/view?usp=sharing

We have another customer reporting that fix in latest Canary doesn't resolve their problem, could you please resume work on this?

Hi all, do we have any updates on this? Thanks. 

szager@, can you please provide an update?

There still appears to be no scroll bar.

This appears to be an issue in the compositor code; re-assigning to bokan@, who has the knowledge.

bokan@
Is there any updated that can be shared with the customer?
do you know any update for M64?

There's no updates, sorry. I'm OOO all next week so I won't be able to look into this more until at least then.

@bokan, still not working on 
10323.62.0
65.0.3325.184
Can you please help to take a look?

I had a look at this yesterday. Unfortunately, it looks like this is just a site that interacts very poorly with the new scrollbar design.

They somehow measure scrollbar thickness on load and create a box below the table that's exactly as tall as the scrollbar thickness. They then use the scrollable content width and create an invisible box inside the "scrollbar box" to that it overflows in the same way. They hook up an onScroll listener to this box and use that to drive scrolling of various boxes in the table.

Android browsers have the same issue but the page has a specific touch listener over the right-most, scrollable columns so they can be scrolled with touch. Unfortunately, they don't have a listener for wheel events.

This would also be a problem on Mac (both Safari and Chrome) since they have similar scrollbars. However, it looks like the page has a workaround for overlay scrollbars there by applying a custom ::-webkit-scrollbar CSS style. This workaround would work just as well on ChromeOS but it appears to be a UA check specifically for Mac :(.

Is there any way to reach out to the developer of the app? The fix is extremely simple on their end - apply the same workaround on ChromeOS as on Mac.

+sgabriel and tbuckley@ for PM side of scrollbars.

@bokan: I will contact the developer with your comments and report back when I get a reply.  However, there is also  bug #778992 , which some of us believe is a duplicate of this one.  I don't have a direct line to that site's developers.

Thanks jwagner@.  bug 778992  is actually different. I'll take another look at it again in the next week or two to double-check the issue and see if we can do something about it in the near term.

In the mean-time, if folks have examples of other pages where scrollbars are broken and they suspect this is the same issue, please file a separate bug and assign to me - I'd like to investigate and determine what issues we're hitting in the wild.

The problem still persists in 68.0.3440.34 even though Google support said that they though 68 might fix the issue.

@bokan: You were going to look at this again back in April.  Can you provide any further info?  Thanks.

Hello!
This bug is receiving this notice because there has been no acknowledgment of its existence in quite a bit of time
- If you are currently working on this bug, please provide an update.
- If you are currently affected by this bug, please update with your current symptoms and relevant logs.

If there has been no updates provided by EOD Wednesday, 12/19/18 (5pm EST), this bug will be archived and can be re-opened at any time deemed necessary.

Thank you!

Our software developer finally fixed this issue for us, and Google closed our support ticket some time ago.  As far as we are concerned this issue may be closed.  Thanks.

Thank you for the update.