1. On Linux ToT, run:

content_shell --root-layer-scrolls third_party/WebKit/LayoutTests/compositing/iframes/become-composited-nested-iframes.html

2. Place the mouse cursor near the top of the first iframe.
3. Scroll down and up repeatedly.

Result: contents of iframes (gray and blue boxes) flickers.

Without RLS, no flickering occurs.
 

Deleted: Screenshot from 2017-10-24 17:16:46.png 18.2 KB

	Screenshot from 2017-10-24 17:16:46.png 18.2 KB View Download

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	Screenshot from 2017-10-24 17:16:55.png 18.4 KB View Download