Amphtml: Unable to scroll on page

[diantekyrie]

What's the issue?

Unable to scroll on page

Briefly describe the bug.
Unable to scroll on page after being able to previously scroll

How do we reproduce the issue?

Please provide a public URL and ideally a reduced test case (e.g. on jsbin.com) that exhibits only your issue and nothing else. Provide step-by-step instructions for reproducing the issue:

1. Go to https://m.aliexpress.com/item/32640703374.html?pid=808_0000_0201&spm=a2g0n.search-amp.list.32640703374&aff_trace_key=&aff_platform=msite&m_page_id=4627amp-i-NUhnrXOPm9ijLvWkMEcQ1557425205007
2. Open developer tools
3. Begin scrolling on page using click and drag

What browsers are affected?

macOSX Chrome Version 74.0.3729.131

Which AMP version is affected?

Dev Version: 1905071607430
Stable: 1904301721170

Is this a new issue? Or was it always broken? Paste the version of AMP where you saw this issue. (You can find the version printed in your browser's console.)

New Issue

cc: @aghassemi, @cathyxz

[aghassemi]

Does this happen on real devices (Android and iOS) or just similator in chrome Dev tools?

[aghassemi]

I can't repro on real devices, but I think I know what's going on. This only happens if mouse down for scrolling happens inside the long amp-iframe AliExpress is including for product description.

@leonalicious I believe this is an issue with the page inside that iframe preventing scrolling via mouse (maybe a mousemove) ( but not a touchmove) is doing preventDefault? ). Could you please take a look from your side?

[aghassemi]

(this could be a Chrome DevTools bug with iframes as well). investigating.

[aghassemi]

definitely a Chrome Devtools bug. Can repro in non-AMP easily with any iframes. will try to find a Chromium bug or file here.

[aghassemi]

https://bugs.chromium.org/p/chromium/issues/detail?id=961426

[aghassemi]

I am going to close this as a Chrome bug.