no default admin account and no privileges for ui apps created by flowable-ui-idm configuration bootstrap if user table not empty

See this discussion in the support forum : https://forum.flowable.org/t/unable-to-login-to-flowable-ui-applications-after-a-fresh-installation/884

If the flowable-rest and flowable-idm applications are connected to the same database and the rest app is bootsrapped first, it will create 3 demo users in the user table, but none of these have privileges to access the ui applications.
If then the idm application is launched it will not create the default admin user account ( https://github.com/flowable/flowable-engine/blob/flowable-6.1.2/modules/flowable-ui-idm/flowable-ui-idm-conf/src/main/java/org/flowable/app/conf/Bootstrapper.java ) and therefore it is not possible to access the ui apps with any of the existing users.