Thanks zachexpress@gmail.com.

Looks like a low-level bug.  Chrome hasn't changed since the fix in M62, still follows the ARC++ suggested way to detect trackpad events:
https://cs.chromium.org/chromium/src/ui/android/java/src/org/chromium/ui/base/EventForwarder.java?rcl=01f34f94caa8753a01e333fca675826c4c45be49&l=58

uekawa@: I couldn't find an internal bug, so commented on b/67300262.  Please take a look.

assigning to hugo


re: #1 which android app did you try? Each app is unique.

I tried android settings app and I can scroll with touchpad 
using the exact same version you specified.

Is this about chrome inside android inside chrome? 
which versions of chrome is the one inside and the outside chrome os?

Strange,

We didn't make any change since yhanada fix in late september (ag/2952946). I verified and this commit is effectively in arc m63 branch. So the android gmail application (com.google.android.gm) is in the compatibility list.

We have multiple users that signal that the touchpad scroll is not working at all in android apps:
crbug.com/780873
b/68842541

These users have this issue on a pixelbook,  zachexpress@ are you also using a pixelbook.

Others users also say that this issue affect any android app, so it may not be related at all with WebView.

In b/68842541 powar@ told us that this bug does not happens intermittently.

We may have a tricky low level bug.

I'm increasing the priority of this bug and will focus on it tomorrow.

fouchal@ what is the status of your investigation yesterday?

Same issue on Pixelbook 128GB running Dev 64.0.3270.0.

Touchpad scrolling is broken on all Android apps including Settings.

I tried unsuccessfully to reproduce this bug on my pixelbook. Other people in chrome os also cannot reproduce this bug. 

Some people report to us that this bug is only intermittent.

seldnplan, zachexpress do this bug also happens intermittently for you? 

seldnplan when you say the Setting application you means the hidden android Settings app or the original chromeos Settings web app?

It's not intermittent here. Just broken. So far I've tested: Flamingo for Twiter, Sync for Reddit, XoDo PDF Reader, Play Store, Play Newsstand, Hangouts, Play Books. Scrolling is broken in all of them, all the time.

For the settings, I did mean the Android Settings app.

Hugo, have you been able to reproduce this issue?

We have had issues before with apps that would cover the whole screen (Such as Twilight), though that would usually affect all touch-based input to android apps. 

seldnplan, zachexpress could you answer a few questions to help reproduce this?
- Do you have any apps installed that could cover the whole screen with a transparent overlay or something like that?

- Do other kinds of touch/mouse input work?
- Is there anything (reboot, logout, etc) that gets this fixed for you?
- Can you also both confirm the exact ChromeOS version you are running?

Thanks! :)

I have not been able to reproduce this bug and i tried multiple different version reported by the users. And no one in the chromeos team has reported this issue.

Nevertheless we have more users that have reported this bug b/68842541 b/69434511. I had a longer offline discussion with powar who is the first to report this bug three weeks ago.

Some user have this bug on M62, others have this bug on M63.

Suppositions:
- Rebooting the device fix the issue.
- This bug only happens on pixelbook.

I'm working on adding more logs to catch this issue. Will update on b/68842541 as this is the first bug.