Schemas (instantly) created just after typing Pretty Name prevents subwiki creation on PostgreSQL 11

STEPS TO REPRODUCE

1. Configure and create a XWiki 11.5RC1 instance with PostgreSQL 11
2. Go to Wiki Index
3. Click 'Create Wiki'
4. Type a Pretty Name for the new subwiki (e.g. subwikiglobal)
5. Select Standard Flavor (or click somewhere on the page)

EXPECTED RESULTS

After the name of the subwiki (and identifier, which is filled automatically) are chosen, the subwiki is ready to be created.

ACTUAL RESULTS

The 'Next Step' button is disabled. Under 'Wiki Identifier' section, the following message is displayed:

A database with this identifier already exists

On PgAdmin (v4.8), under 'xwiki > Schemas' the 'subwikiglobal' is already created (instead of being created when clicking 'Next Step > Create'). If another subwiki Pretty Name is typed, its schema is automatically (instant) created as well, thus preventing subwikis creation.

The issue could not be reproduced in XWiki 11.4