@admin > listfields: always expand after save

Hi,

when I collapse list fields within the admin and then hit save, they are all expanded again. A bit annoying when you have lots of complex lists.

Start by reproducing the admin list-fields behavior: collapse several complex list fields, save, and observe whether they expand. Trace the admin save and list-field state handling to identify the relevant entry point; done means collapsed fields remain collapsed after saving.

Written by the indexing model from the issue text.