Broken theme mods option

[grogou]

Description

When activating Anyone can register option from wordpress settings, theme_mods options goes broken on db.
It's i guess can be with FSE.

Step-by-step reproduction instructions

1. Activate some FSE theme for example TT1 Blocks theme.
2. Go to General settings and activate Membership ( Anyone can register )

Screenshots or screen recording (optional)

WordPress information

• WordPress version: 5.7.2
• Gutenberg version: 10.7.4

[Sandstromer]

I had a similar issue that may be related.

Was trying out a membership plugin in conjunction with a FSE theme and all was working good before 10.7.3.

After updating Gutenberg to 10.7.4 (not 100% sure whether the error appeared in 10.7.3 or 10.7.4 as they were released very close together) I got the Warning: Illegal string offset 'custom_css_post_id' in ..\wp-includes\theme.php on line 1063 error.

Checking the options table showed the theme_mods_themeslug now had an option_value of "-", so I deleted that row and it was automatically re-added correctly, and all was good again.

Think it might be something to do with #32229 but not sure exactly how.

[Sandstromer]

Just to add that all my another installations that did not have any membership plugins nor the 'Anyone can register' option selected, were okay after updating to 10.7.4

[aristath]

This was a bug in a couple previous versions and it was fixed. @Sandstromer is right, this was due to changes in the site-logo block. #31994 is the PR that broke it, #32229 is the PR that fixed the issue.

[Mamaduka]

I think we can close this issue.