This is way too complcated, as I need this at many places.
I believe we have to create a new actionpart for this. A simple "Fade to" actionpart including a delay - and maybe with the possibility to choose a color. This way you could easily fade to a specific color, without using scripts, shaders, masks or upscaled images.
Fine if you want an action part for that, then I want a new option for selecting a mouse cursor to display during cutscene, cursor hide/show events & display texts, etc. I hate that the mouse cursor disappears. Would prefer to show a loading cursor icon or a semi-transparent version of my default cursor.
Why is it too complicated?
shaderLightness() function is very easy to use as would setting up an interface with a black background the size of your default game resolution that you could fade in/out as needed.
P.S: there is a shader function for tinting the screen a certain color too, but I don't know if you can tint solid colors or just semi-transparent tint. It's not something I've used, but Simon would know.