Image quality in thumbnails

I wanted to make sure I haven't missed a setting in the options before I submit a bug report.

I get image corruption in thumbnails and then when I open the image it sharpens to proper quality.

I took some screenshots to illustrate:-

Thumbnail -

Thumbnail

Fully loaded image -

Fully loaded image

Anyone got any clues? Is there a setting I've missed or is this a bug?

2 comments

I swear there was a setting for this somewhere.
- The only option I could find was settings>media>advanced>limit download size which I toggled off but nothing changed.