Created attachment 139065 [details]
Invert Selection proposal in menu

SUMMARY
Improve the selection capabilities. Enable Invert Current Selection. When a selection is created, should be an option to invert the current selection (Square, Elliptical or Free-Form) to the complementary area. 

STEPS TO REPRODUCE
1. Use any of the selection tools. (Square, Elliptical or Free-Form)
2. Select a region of the image
3. [new] Invert the selection current to the complementary area. 
4. Apply a selection feature [for example, more effects]

OBSERVED RESULT
Selection will be a new area, outside the former selection. The complementary area. For example, if the original selection was a square, the (new) inverted selection will be all the area outside that square. 

EXPECTED RESULT
In the new area selected (invert area) to be able to use the selection menu features, also apply the effects to modify the new area, for example, adjusting saturation and other color settings, flatten, sharpen, etc. 


SOFTWARE/OS VERSIONS
Version 19.12.3
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
It will be so useful to have this new feature in the right click contextual menu besides  "invert Colors" now "Invert Selection" [see attached screenshot image]