Not getting outdated. It's just a recent error in latest update of these docs.
Two months ago I suggested Chris to make 2 separated lists of plugins, backend and frontend ones (before that, they were mixed), but apparently he had some cut-paste error, and no one realised till now. :-)
So:
- theme-header and theme-footer should be in FRONT-END list.
- header and footer should be in BACK-END list.
EDIT: These errors have been fixed.
Two months ago I suggested Chris to make 2 separated lists of plugins, backend and frontend ones (before that, they were mixed), but apparently he had some cut-paste error, and no one realised till now. :-)
So:
- theme-header and theme-footer should be in FRONT-END list.
- header and footer should be in BACK-END list.
EDIT: These errors have been fixed.