Cannot delete the last item in a list in a theme

[artofthesmart]

Looks like there's a glitch where the last item in a list theme setting cannot be deleted.

Steps to reproduce:

1. Install Grav + Admin.
2. Install the Hypertext theme, a bare-bones theme with a list item in the 3rd tab. Theme blueprint YAML file, see line 266.
3. Add a few off-site links. Save.
4. Delete all but one link. Save.
5. Delete the last link. Save.

Expected Behavior: The list will be saved as empty.
Actual Behavior: The page refreshes and the last list item is still in the list.

What I've tried

1. Double checked that the permissions on the /user/config/themes/hypertext.yaml file are correct and editable by the host user/group. No change.
2. Double checked that there are no "Default" links in the hypertext.yaml file that comes with the theme, that might be overwriting the emptiness with some default. Nothing there.

[mahagr]

Yes, this is known bug as when the field gets empty, it sends no data back, which is considered to be "field was not sent".

This bug has already been fixed in pages in Grav 1.7, which uses Flex Objects and Form plugin, which has the fix.