I tried this under PopOS. Many of the steps can be removed.
This requires the Linux terminal do at your own risk.
Just install libserialport0, patchelf, and arduino. sudo apt install libserialport0 patchelf arduino
Run Arduino and it will bug you to be added to the dialout usergroup. Confirm and it will ask for your password. After that run:
sudo patchelf --add-needed /usr/lib/x86_64-linux-gnu/libserialport.so.0 /usr/lib/x86_64-linux-gnu/liblistSerialsj.so.1.4.0 in the terminal
In your Playdate Mirror directory, rename libserialport.so.0. to libserialport.so.0.bak and Mirror should work.