As the title suggests, I flashed J-Link OB onto the EDBG of the M0 Pro. J-Link works, debugging works, but this broke Arduino IDE. Personally I actally prefers J-Link's debugging of ARM targets, especially its superb integration with GNU MCU Eclipse.
Is there any way to recover from that? Or on the other hand how to modify Arduino IDE to work with J-Link OB on EDBG?