> Yes - except this is HTTPS cache - and takes screenshots of your HTTPS data.
HTTPS is also cached by every major browser, meaning the image in question would be in your cache just as well as the screenshot containing it.
> Its silly because they turned off viewing the HTTPS websites on the 'newtabs' and replaced it with grey screens - yet they still take the screenshot.
If this is true you should file a bug for it. Bug 754608 / Bug 627239 / Bug 822867 suggests that this is not the case, and that capturing them was disabled entirely. In fact, those three bugs suggest that this bug is only open because a better replacement for grey-squares is needed?
> The sec-low status was given because they mention the low res screenshots are not enough to get anything useful - but I've just proven that not true.
This does not seem to match what I see on the thread. The bug was filed by a mozilla developer and the consensus seems to be that it is definitely an issue:
c0 - Mozillian files the bug
c4 - Mozillian mentioning they think screenshots of any size could be sensitive -- the opposite of "not enough to get anything useful" -- but also that it's not something that can be reasonably fixed.
c5 - Mozillian acknowledging its a problem and suggesting its difficult to properly fix
c8 - Mozillian noting this is an even bigger issue on OS X
c9 - Mozillian noting that the whole concept might need rethinking
c11 - Mozilla security manager assigns security classification to bug