Well migrating to Python 3 seemed all too easy. A few code changes here and there and the new version was passing all tests nicely. But then I started getting reports that the Win10 version didn’t start – and with an empty logfile there was little to go on. It worked fine on my build PC, but then the environment on that is not representative of a fresh Windows installation. So a Win10 virtual machine was built under VMWare for testing.
With a bit of work, it was found that the Python initialisation had broken with Python3. It needed to find the default libraries, which are shipped with the Windows build in the Python38 directory. Now Glade sets the PYTHONHOME location to this directory internally, but after Python initialisation. Rearranging the initialisation order, plus fixing some Unicode issues, fixed the problem.
Thanks to those that reported it – much appreciated!