Doh! Plugin conflict! ‘Figures…
I usually don’t activate two plugins at once. That’ll teach me.
So… The “Series” plugin failed to activate, after “Organize Series” was activated. “Series” does activate after I deactivate “Organize Series”. Then, if I try reactivating “Organize Series” (with “Series” active), I get the following error:
Fatal error: Cannot redeclare in_series() (previously declared in …/wp-content/plugins/series/template-tags.php:112) in …/wp-content/plugins/organize-series/orgSeries-template-tags.php on line 603
Sounds like they both use the same taxonomy and/or the same
The series I created with “Organize Series” doesn’t show up when I deactivate that plugin (“Organize Series”) but does appear when I activate this one (“Series”).
So it sounds like a plugin conflict based on taxonomies and/or a single function.
As is often the case, it’s difficult to decide which plugin to use. The advantage of “Series” is that it’s developed by someone I trust. The advantage of “Organize Series” is that it was recently updated.
Now that I see my error, I’ll give “Series” its fair chance, especially since the “series metadata” (the inclusion of a post in a given series) seems to be maintained across plugin changes.
It also allowed me to notice that the default “Twenty Eleven” theme doesn’t support sidebars on single posts. Sounds like a very weird thing for a theme which is likely to serve in troubleshooting. What gives, WordPress team?
Thanks again, greenshady! For a 0.1 non-commercial plugin which wasn’t updated in a while, this is premium support!
And sorry for my absentmindedness.