[DiapDealer]

We can still build 5.15 from source with the open-source license, right? It was my understanding that only the precompiled binary installers were reserved for commercial users.

It was always my plan to eventually move to Qt 5.15 LTS, since we build Qt from source anyway for Windows and Mac (much like Arch is doing already) as long as it works OK. But perhaps I'm missing something about why we should stay away from building/using the latest LTS source ourselves?

I've not updated my Arch system to Qt5.15 yet. I'll have to do some testing before I can determine what might have gone wrong with it and Sigil. It's possible the Sigil package on Arch might need to be rebuilt for Qt5.15. It had to be rebuilt for Python 3.8, for instance. If so, I'm sure they'll do it soon. In the meantime, I should be able to manually rebuild Sigil with the updated system Qt this weekend.