it is really a good idea to use overlay effects and inks for Bidge's problem, as LC is *very* fast with applying that (rather than processing the imageData).
But don't forget, connected to inks:
= not all inks work the same on all platforms (e.g. linux has some problems with the opacity of the stack window when using ink "blendDstIn" -- could be used as feature, kind of windowShape)
= there was a change in Skia (the lib that LC uses) and by that the bitmap effects, that are still in the menus for inks, were removed starting with 9.0.0-dp7:
## Update Skia (graphics library) (9.0.0-dp-7, Release notes )
This major Skia update improves both rendering quality and performance. It also opens the door to substantial future improvements and feature additions. In order to allow this, support for certain legacy drawing features has had to be removed. In particular, legacy blend modes (also known as bitmap effects) are no longer supported.