Transaction isolation level configurable per account/user

It would be interesting to have the default transaction isolation level configurable on an account or user level (similar to max_statement_time or max_user_connections).

Many customers want to consolitdate their zoo of applications into one mariadb server. but some of the applications require a different isolation level (read committed) than default (repeatable read). Because those are commercial products (atlassian tools for example). the code is/cannot be changed.

The result is, those tools cannot be consolidated OR all the other applications have to cope with the trx isolation level read committed. which is uncertain if it works.

This could also be an interesting requirement for mariadb cloud providers...