Symlinks + UMU Runner

[DocMAX]

I noticed that Steam Proton is creating compdata dirs (prefixes) with symlinks to most Windows DLLs. Can UMU Launcher do the same to reduce Prefix Size?

[loathingKernel]

It's not umu, it's proton-ge and other custom protons that use protonfixes that do this. It has been discussed internally a lot. The issue is that some windows libraries will fail to install or work if these internal dlls are symlinked, and that's why everything is copied instead.

Umu has nothing to do with any of this.

[DocMAX]

Gia sou (me greek too :-) )
If i would impement this functionality how can it be done with UMU?

[loathingKernel]

Umu cannot affect this in any way. It's up to the proton you use.

[R1kaB3rN]

umu-launcher delegates prefix creation to the Proton build which is where the final size is determined. As for anything prefix related, this tool only creates some files to prepare for that creation.

However, if your real concern is about optimizing disk space, the current suggestion is to use either a single prefix (e.g., umu-default) and accept the risk or use external tools.