If I try to add a custom link to a menu, it says “Pending” and won’t save. If I hit save, it disappears. This only happens to custom links – pages, posts, categories all work fine.

I’ve googled this issue and they suggest switching to a default theme and back, or repairing the wp_postmeta database. I’ve done both with no success. No clue what to do next, and this is driving me mad. I’m a beginner too…