TYPO3 Core

The middleware should detect that loop, fullfilled by pure
`ext:redirects` records and dropping the redirect(not doing)
it - along with logging it to the log.

Additionally, the integrity check should detect that. There
is a pending patch #99485 to make that integrity status visible
and searchable/fiterable in the admin/backend module (later on).

However, if a editor changes a page slug a normal notification
should appear if auto-redirect creation is enabled, at least
the core version. That misses a redirect loop detection at that
specific point.

Due to talks with quite some people, it's clear that that notification
is already not really understood by editory and adding that sentence
would not really help here.

Beside some contributor efforts now, I have some features in mind for
v13 to enhance the visibility of these redirects on pages - will see
how it pays out. Beauce of planing and timing thats scheduled for a
later point in the v13 development cycle (after 13.0 / 13.1).

I had quite some issue to understand this issue first, if this is now
what really:

• bug-report: what's not working excalty ? Redirects not created,
  Endless Loop Detection and Preventing in the Middleware broken ?
• feature-request: Enhance visibility, notifcation etc