Weblate database switch to PostgreSQL
Upstream only wants to support PostgreSQL and kick out MySQL support. (see https://github.com/WeblateOrg/weblate/issues/2825, https://docs.weblate.org/en/latest/admin/install.html#database-setup)
Currently PostgrSQL is only recommend for new installation and existing users don't need to switch atm.
On the bugreport the have a link to a migration guide: https://www.calazan.com/migrating-django-app-from-mysql-to-postgresql/