The same way we have add, multiply and subtract blend modes on vse strips, I would like to add Screen and Overlay as they are very useful.
Updated: After a lot of feedbacks and productive discussion from you guys, I added a single Color Mix effect and the default strip Blend Mode having the blend modes defined em 'BLI_math_color_blend.h' as suggested by @sergey.
Warm Regards and thanks for blender!!
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