After importing a series of posts (using WP All Import), my (custom) page template is unable to access the post's contents/fields. However, if I open the post in the editor and click "Update" without making any changes, the page template suddenly works perfectly. This makes me assume that some previously non-essential and previously empty database field is inserted.
Although this "bug" is probably due to a nuance in either the Advanced Custom Fields plugin or WP All Import plugin, my testing still suggests that some very minor database state change is happening after clicking the update button (even without making any changes).
Edit: FYI after importing posts, I've tried deactivating all plugins and the issue still persists.
Edit #2: After more testing, it seems that WordPress generates _fields after manual "updates" but not during the import process. Example, importing data into field
full_address WordPress will create a
_full_address only after a manual update. I'm doing more testing now, but this might be the problem.