Just taking a look at phab.wmflabs.org, there is no clear indication for me that it is a testing instance. It should be more clearly marked as such, with potentially a "description section" (as is used to hold links and information on this instance) indicating that it is a testing instance.
Description
Description
Event Timeline
Restricted Application added a subscriber: Aklapper. · View Herald TranscriptMay 18 2021, 4:28 PM2021-05-18 16:28:36 (UTC+0)
JJMC89 edited projects, added VPS-project-Phabricator; removed Phabricator.May 18 2021, 4:51 PM2021-05-18 16:51:52 (UTC+0)