Black boxes

[Mad Doug Biker]

On my two devices (mobiles), there occasionally are black boxes and lines that suddenly appear and flash, blink and flicker on my screen at random speeds and parts of the screen.
I have noticed it on some other websites too.

They are extremely irritating and will disappear for a few seconds if I scroll the page a little.

Any idea what this is and how to fix it?

Thanks.

 

[Mad Doug Biker]

Erm... HELLLLOOOO?!

 

[Bollo]

Sorry, tried reading your post but there were black boxes and lines everywhere!

Smells to me more like an issue with the underlying OS or browser than anything to do with this or a range of sites. Are both mobiles running the same operating system and browser?

I would have said a screen issue, but it’s unlikely to affect two screens in the same way at the same time.

It’d be quite a bit if work to deliberately code a page that behaved as you describe. Certainly not a defect that creeps in!