And while you were out there getting distracted, Nick has ported XDG Portal/libei support to synergy so it can be run under Wayland now:
@whot This looks like Flatpak/GNOME support, and not proper Wayland support. The implementation relies on Flatpak-specific APIs with no portable implementation. I wish they'd label it as "GNOME support" rather than "Wayland support" which is just misleading.
@whot thanks for the reminder. I’ve given Nick a hard time for promising this years ago, I need to spend some time testing this soon.
@whynothugo There's no "proper wayland support" for input capture/emulation. It's outside the scope of the core protocol and there's no commonly supported wayland extension for it.
It uses the XDG Portal APIs and the implementation behind those which means right now it should work on gnome and kde *under* Wayland, possibly others that I'm not aware of.
Once clipboards and whatnot is implemented it may become more waylandy though.