Flickering and CPU usage caused by blocked images

gorhill / uMatrix

uMatrix: Point and click matrix to filter net requests according to source, destination and type

GNU General Public License v3.0

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Flickering and CPU usage caused by blocked images #909

Closed Hyundy closed 6 years ago

Hyundy commented 6 years ago

Example URL: https://www.reddit.com/r/firefox/

1.2.0 Firefox 58 (behaviour seen on Linux and Android)

The text displayed in the placeholder of a blocked image will sometimes move up and down slightly. On some pages like the above, this causes the rest of the page to move up and down slightly.

gorhill commented 6 years ago

When you block stuff, expect pages to not render perfectly pixel-wise.

Hyundy commented 6 years ago

I think this is actually a change in Firefox that causes this, not uMatrix, as I first thought.

Although, I can only reproduce it with uMatrix and not uBlock Origin, in clean and old profiles ("Hide placeholders of blocked elements" in uB was turned off).

https://imgur.com/a/3kjyo

Two examples.