Usually, the fact that I want to take a screenshot is first in my mind, and then the scope of what the screenshot should contain comes second. So what ends up happening is that I'll hit PrtSc, realize that I want to include my entire screen, and then have to take my hands off the keyboard to grab my mouse.

It would be nice if using the keyboard shortcut ctrl+A would create a selection that c

The Invert Colors option in the menu bar currently takes a lot of time to give an output (especially on larger screens). Because of this, the application gives the user an illusion that it has frozen and the user might quit the application, losing his/her progress.

A suggestion to this would be using the flood fill algorithm which is already being used in the fill bucket feature.
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