SyncTrayzor (windows client implementing synching) is pretty nice. It runs as a tray icon but when you click it, it loads like a native app even though it's a web app (similar to electron)
But it is still a web ui, not a native one. Also, SyncTrayzor itself is not cross-platform, so Linux users have to install syncthing-inotify for watching the directories for changes.
It's network compatible with and syncthing clients. Syncthing is an open standard with dozens of client apps.
My thoughts exactly. I might give this a spin. Here's hoping it has "Folder Master" support.