When opening an image which was downloaded from Facebook, I received a prompt saying:

"The image [...] has an embedded color profile:

"sRGB IEC61966-2-1 black scaled

"Convert the image to the RGB working space? [...]"

I told GIMP to "keep" the colour profile, and it accepted my answer but editing was very slow, to the point where it was hard to do any work.

When opening the second time and agreeing to the conversion, editing resumed its normal pace.

This may or may not apply to all Facebook downloaded images.

Suggestion: If the slowness is not a bug, but a necessity due to circumstances, perhaps add a comment to the "keep" button saying "(Editing will be slow)". Less experienced users may otherwise find it hard to identify the mismatching colour profile as the source of the slowness.

Regards, Johan Förberg