It's very important for me for the text to be clearly visible when added to a screenshot. This is usually easily achieved by using black text with white background or white text with black background - but other colours usually look good with either (except maybe for very dark and very light colours).
I know that usually the implementations involve:

• Creating a shadow
• Creating a border

I

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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