Thanks a lot for your contribution! Could you please provide some steps to reproduce the error?

Here the steps to reproduce:

• enable error reporting in moodle by adding these lines in config.php:

ini_set ('display_errors', 'on');
ini_set ('log_errors', 'on');
ini_set ('display_startup_errors', 'on');
ini_set ('error_reporting', E_ALL);

• add a new kanban board in a course
• click the 3 dots/edit details of the first column
• in the browser (firefox) shows "JSON.parse: unexpected character at line 1 column 1 of the JSON data"
• In the error.log of apache you can see like that:
  ``[Mon Aug 26 11:50:15.454348 2024] [proxy_fcgi:error] [pid 48548] [client 127.0.0.1:56594] AH01071: Got error 'PHP message: PHP Warning: Undefined property: stdClass::$autoclose in /var/www/html/moodle.ts-umwelt.de/mod/kanban/classes/form/edit_column_form.php on line 125; PHP message: PHP Warning: Undefined property: stdClass::$autohide in /var/www/html/moodle.ts-umwelt.de/mod/kanban/classes/form/edit_column_form.php on line 126', referer: http://localhost/moodle.ts-umwelt.de/mod/kanban/view.php?id=3382

I hope this can help you :-)

Thanks again and sorry for the delay! I think this could be fixed in a shorter way using the ?? operator.
There is also an additional commit from #58 in this pull request. Could you please take care about this?