Can anyone tell me whether the epub spec's require the attributes to be listed in any particular order? I tried to wade into
the OPF specs, but soon realized I was in over my head. Nevertheless I didn't see anything suggesting that the attributes had to be in any particular order.
That said, I prefer the order provided in Sigil 0.3.4 just on the basis of readability.
But if order DOES matter, this should also be reported to
Sigil's issue tracker as well. Maybe it should be reported there anyway, just for completeness.
And thank you Bertrand for finding this out. Yet another quirk to be aware of when trying to prepare epubs that work for arbitrary reading systems.