Is your feature request related to a problem? Please describe.
At the moment, I have to either modify the source code and recompile it, or inject dlls into the shell in order to modify its behaviour.

Describe the solution you'd like
A plugin system with a flexible API, for modifying the behaviour of the shell.

Describe alternatives you've considered
I can hook into it, but that is a hack. Also recompiling is an option but pretty annoying, as you have to merge changes when new versions come out.

Additional context
I do not expect this to be added for the moment, but I'd like for this to become a thing, at some point.