[KevinH]

Hi All,
I am looking for some input from users on a change in how semantics are managed for epub3.

Right now for epub3, Sigil properly puts and updates semantics in the nav landmarks but tries hard to keep the older (actually deprecated in epub3) guide section of the content opf in sync.

Unfortunately, if guide and the nav landmarks are ever at odds, the sync is lost forever (or until the content.opf guide is manually edited).

To prevent these issues for epub3 users, I would like to stop trying to keep the guide section of the opf updated at all under epub3. But then add a new epub3 tool menu "Generate Guide from Nav Landmarks".

That way if a epub3 user wants to create an epub3 that is very compatible with older epub2 reading devices, they can simply use "Generate NCX from Nav" and "Generate Guide from Nav" epub3 tools to automatically rebuild a correct ncx and correct guide section in the opf before saving.

If we decide to go that way, for epub3 users we could in fact automatically run all 3 epub3 specific tools on any Save or SaveAs:

1. update epub3 manifest properties
2. generate NCX from Nav
3. generate OPF Guide from Nav

thereby building an epub3 epub that will be as correct as possible and as compatible as possible with epub2 readers automatically.

These proposed changes would not change anything for people creating epub2 epubs at all.

Thoughts on these proposed changes and thoughts on automating backwards epub2 compatibility when saving epub3's are welcome.