Resolved, partially.
The Fix:
- Browse to the talk page that won't load Flow, Portal_Talk:Welcome
- Delete the Talk page using the Delete tab.
- Go to Portal:Welcome
- Click Discuss.
- You get Flow.
Apparently, even though the talk page appeared empty, something was remnant that was breaking Flow.
I re-validated my fix above, to put Flow declarations after protection, and it turns out that has no effect.
Still broke:
Now i'm getting Flow on all Talk pages EXCEPT Main and Form talk pages.
AM getting Flow on Category and Help talk pages.
I'm thinking this might be related to constants. My Flow declares are:
$wgNamespaceContentModels[NS_MAIN_TALK] = 'flow-board';
$wgNamespaceContentModels[NS_FORM_TALK] = 'flow-board';
$wgNamespaceContentModels[NS_HELP_TALK] = 'flow-board';
$wgNamespaceContentModels[NS_CATEGORY_TALK] = 'flow-board';
Maybe NS_HELP_TALK and NS_CATEGORY_TALK are defined in MW core, while NS_MAIN_TALK and NS_FORM_TALK are NOT defined in core.
Anyone know if that's the case?
Update, further fixed:
Yep. NS_MAIN_TALK is incorrect. It's just NS_TALK. Extension default namespaces#MediaWiki Core
Now the only namespace giving an issue is Page Forms' NS_FORM_TALK. The manual says Page Forms Talk NS is PF_NS_FORM_TALK. However that's not working. So instead of the constant, i tried the actual number: 107. That worked.
So far, it looks like i'm now getting Flow on all talk pages.
I'll mark this resolved after more testing.