Barrier is a free and open-source KVM forked from Synergy. It mimics the functionality of a KVM switch. It allows you to use and share a single mouse and keyboard across multiple devices. For instance, my macOS (server) and Ubuntu (client).
For Windows and MacOS (brew install barrier), the latest packages are available here. Ubuntu: sudo snap install barrier. Arch: pacman -S barrier.
MacOS: Server (share this computer’s mouse and keyboard). Click on Configure Server…
Drag and drop the computer icon from the top right to a suitable position. The position is essential because that’s how your mouse pointer will move between screens. Observe that you should provide the hostname of the client computer.
Barrier
Ubuntu: Client (use another computer’s mouse and keyboard). Disable Auto config. Screen name: MyLinux. Server IP: 192.168.1.40 (my MacOS’s IP).
Maybe you could set up Barrier to run on startup. Launch Startup Applications: Name (Barrier), Command (/usr/bin/barrier).
Set Barrier to automatically launch at boot up (macOS). Go to System Preferences and click Users & Groups. Then, click on Login Items. At the bottom left corner of the window, click on the lock icon and enter your admin password. Click the plus (+) sign, Applications and select Barrier to auto-start.
#!/bin/sh
/usr/bin/barrier -f --no-tray --debug INFO --name nmaximo7Arch [192.168.1.40]:24800 &
It means, -f: run in the foreground; ‐‐no-tray: disable the system tray icon; ‐‐name nmaximo7Arch: use nmaximo7Arch instead of hostname to identify this screen in the barrier’s configuration; [192.168.1.40]:24800: server’s dirIP:port.