Finish adding documentation for running with pyside6 #1271
Description
What's the problem this feature will solve?
Add setup instructions and other information about running on pyside6.
Also clearly indicate in code (in searchable way) areas that have different logic depending on if using pyqt5 or pyside6
Describe the solution you'd like.
Initial docs are in-progress in this patch: #1214
Additional context.
No response