Twenty Twenty-One: PHP warning: Illegal string offset 'custom_css_post_id'

[karenaug]

Hello,

When I open my blog, I get the following error message:

Warning: Illegal string offset 'custom_css_post_id' in /.../wp-includes/theme.php on line 1063

In the dashboard I see the following message:

...ng offset 'nav_menu_locations' in /.../wp-includes/theme.php on line 1063


Warning: Cannot modify header information - headers already sent by (output started at /.../wp-includes/theme.php:1063) in /.../wp-includes/functions.php on line 6362

Line 1063 is $mods[ $name ] = apply_filters( "pre_set_theme_mod_{$name}", $value, $old_value );

I have tried: uploading wordpress again with ftp, clearing caches, reinstalling the twenty twenty one theme, deactivated plugins, uploading the theme.php file again.
I don't see this bug when I activate other themes.

The forum thread is: ​https://wordpress.org/support/topic/theme-down/page/2/#post-14525964

Is there anything else I can do?

Kind regards,

Karen

[sabernhardt]

@karenaug Hi and welcome to Trac!

Your site still uses Twenty Twenty-One, and the custom CSS is included properly now. Were you able to fix it somehow?

I received similar errors with Twenty Twenty (and possibly Twenty Nineteen as well) around the time you opened the support topic and this ticket. I think the errors occurred immediately after activating a plugin, though you said that was not the case when you had trouble. (Because my site was a local development site, on WP5.8-alpha, I replaced it entirely.)