The core change that caused this failure was #3232673: \Drupal\Core\Entity\EntityInterface::label() can return a NULL → , which was committed on 30 Sept 21 (commit 9da1866). That issue added an assert() into the core filter module to ensure that all FilterFormat entities has a label. This was not explicitly checked in prior versions of core.
This code in address module that is causing the error is :
$this->testFormat = FilterFormat::create([
'format' => 'test',
'weight' => 1,
'filters' => [
'filter_html_escape' => ['status' => TRUE],
],
]);which creates the FilterFormat with an id but no label.
Its missing the 'name' key in the array parameter.
Run CountryNameTokenTest.php in a Drupal 9.3.0-alpha1 environment.
Add name key to array.
Fixed
1.0
Code
Not all content is available!
It's likely this issue predates Contrib.social: some issue and comment data are missing.