Undefined index: #format in Drupal\filter\Element\TextFormat::processFormat()

Since there hasn't been a follow up to #5/#6 going to close for now.

If still a valid bug please reopen updating issue summary with steps.

Thanks all!

I'm getting the same warnings on a webform that is placed in a webform block in a layout. Anonymous users don't have access to the Rich Text text format, and the webform is (or will be) available to anonymous users.

My webform contains two processed_text elements with '#format': rich_text and one text_format element, with '#allowed_formats': rich_text: rich_text.

Site specifications are:
Drupal 9.5.10
PHP 8.1
webform 6.1.5

Updating webform to 6.2.6-beta6 won't help since $element['#format'] is still written in core/modules/filter/src/Element/TextFormat.php, and $element['#format'] does not exist for anonymous users. If I add anonymous users to the Rich Text text format, the warnings go away, but doing so is not a possible solution.

The warning is being thrown when I switch the theme to Olivero.

This patch may solve the problem. Submitted it for testing.

Missed one. Updated patch.