010101 can you clarify which column was affected by the error? You mean the
error column on
kilowhat_rich_embeds ? I'm a bit confused because that column is not supposed to be a key at all so there shouldn't be any opportunity for this error to arise.
If you have any error related to the
url_hash column, please let me know. Changing the index or column type of that column might break the extension.
If the error relates to the
url column, it doesn't really matter because the index on that column is then deleted by one of the migrations that follow. That column should stay utf8 though.
If the problem relates to the key name, maybe your database table prefix is too long?
EDIT: please include your MySQL/MariaDB version information. You can run
select version() as version via SQL on the SQL server, and I think this information is also shown in the
php flarum info output and the admin dashboard.