Access denied for user 'c2_test_wp'@'localhost' to database 'c2_test_wp'

short description

A newly created DB user has no access to the database.: Access denied for user 'c2_test_wp'@'localhost' to database 'c2_test_wp'

The issue seems to be caused by escaping of the db name:

SHOW GRANTS;
GRANT ALL PRIVILEGES ON `c2\\_test\\_wp`.* TO 'c2_test_wp'@'localhost'

correct behaviour

User should have access to the database.

environment

Server OS: Ubuntu Server OS version: 20.04 ISPConfig version: 3.2b1