Around March of last year it was fixed. Then sometime around October the video
tearing started occurring again after an Nvidia driver update. I don’t have
driver version numbers, sorry.
I definitely believe it is an Nvidia driver issue. There is no screen tearing
on my late 2012 Dell XPS 13 Intel hardware with the same software setup and
open source Intel drivers.
Desktop effects / compositing needs to be disabled for this to show (because the compositor might do its own vsync.) In fullscreen, compositing is temporarily suspended, so in that case it shows in fullscreen. (In KDE, enable the “Suspend desktop effects for fullscreen windows” option.)
I don’t see any screenshots there. But the Chrome bug reports links to the Wikipedia article about tearing, with a simulated screen capture. This is what it looks like:
Since you said that people posted screens, this might be something different, since tearing cannot be captured in a screenshot. It’s an effect that manifests on the monitor and can only be photographed.
It appears that if I navigate to chrome://flags/ and enable the “Override software rendering list” option I no longer get tearing. Somehow after Chromium version 22 some Nvidia setups aren’t recognised as valid system configurations for hw decoding.
OP - try this, it seems to be the Pepper Flash alternative to OverrideGPUValidation=1