We believe a user should be free to use any plug-in, regardless of license, as long as
- the plug-in specification / API is open and compatible to both PopTracker's license and the plug-in's license, for example in a separate repository licensed under MIT,
- the plug-in does not embed any PopTracker code at compile-time,
- the plug-in is not required for PopTracker to function and
- the plug-in is installed separately.
If this is found to be incompatible to GPLv3, this shall be an exception to PopTracker's license.
To avoid edge cases, it is preferred to ship plug-ins as separate executables that communicate with PopTracker, with all communication defined in an external, license-compatible specification.
Plug-ins that are fully license-compatible do not fall under those restrictions.