x11-misc/synergy-2.0.0 is a beta build of the symless synergy application that hasn't been updated in 2 years on git and is no longer supported by symless. Symless has version 1.14.1 available as .RPMs and .DEBs available to download from their website which they are currently supporting and I have verified works as intended on my machine. I got the file from here: https://symless.com/synergy/downloads . I installed the .deb by extracting the data.tar.xz and running tar xvf "path\to\data.tar.xz"