It turns out that I only tested the markers pull request #9 on a computer with PyQt5.
I just tried using it on a computer still running PyQt4 and it crashed (sorry, didn't think to save the error message, something about not being able to check a NoneType or similar). Updating to PyQt5 resolved this.
We should either officially cut support for PyQt4 (i.e. don't try to import it, and if it's there but PyQt5 isn't, print a message advising the user to upgrade), or fix the code to be backwards compatible.
Original report (archived issue) by Shaun Johnstone (Bitbucket: shjohnst, GitHub: shjohnst).
It turns out that I only tested the markers pull request #9 on a computer with PyQt5.
I just tried using it on a computer still running PyQt4 and it crashed (sorry, didn't think to save the error message, something about not being able to check a NoneType or similar). Updating to PyQt5 resolved this.
We should either officially cut support for PyQt4 (i.e. don't try to import it, and if it's there but PyQt5 isn't, print a message advising the user to upgrade), or fix the code to be backwards compatible.