> It is claimed Synergy 3 will arrive in 2022 or 2023, which I expect (no insider info) will likely be a lipstick-on-a-pig Electron UI around the same buggy core they've been prodding for 10 years without substantial enhancement.

They claim they are hiring Node.js and React developers to deliver something with "the rock-solid stability of C++".

So I'd wager you are correct with an Electron UI.