[DOCS] Outline ext:felogin behavior when plugin is hidden at login

This change moves the section about "Access restrictions on the felogin
plugin" to the user manual, since the section is not an example, but
an important notice for users of the plugin. The part about having
two plugins on one page has been removed, since this will lead to
other problems as noted in the "Known problems" chapter.

Additionally, a short notice about the "Hide at login" problem has
been added to the "Known problems" chapter.

Resolves: #100632
Releases: main, 12.4, 11.5
Signed-off-by: Torben Hansen <derhansen@gmail.com>
Change-Id: I28fe311ce46ef3e1cae9cd60cebb7215fb02701e
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/79543
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Benni Mack <benni@typo3.org>

typo3/sysext/felogin/Documentation/Examples/Index.rst

@@ -67,27 +67,3 @@ id=2:
    [end]
 
 Of course there can be solutions with :typoscript:`HMENU` items, etc.
-
-
-.. _access-restrictions:
-
-Access restrictions on the felogin plugin
-=========================================
-
-A very common issue is that the felogin plugin is set to Access: Hide
-at login. After the core has processed the login request the page will
-be rendered without the felogin plugin. If there are redirect options
-active they will NOT be executed, simply because the felogin plugin is
-hidden.
-
-One solution is to insert felogin with TypoScript in the page. The
-redirect options must be set in the TypoScript configuration. Any
-output of this plugin can be hidden with CSS. Redirect options will be
-executed by this invisible felogin. If there are two instances of
-felogin present on a page (one as a content element, the other via
-TypoScript) this can easily lead to problems, just as with any plugin.
-
-Of course setting the felogin plugin to Hide at login and having
-redirect options together doesn't really makes sense if a redirect
-will happen in all cases.
-

typo3/sysext/felogin/Documentation/KnownProblems/Index.rst

@@ -14,3 +14,7 @@ Known Problems
   stored and only one of the forgot password forms will work. Make sure
   there is only one felogin plugin on the page where the password
   recovery form is displayed.
+
+- If usergroup access rights of the plugin are defined to
+  :guilabel:`Hide at login`, all felogin code (e.g. redirects, PSR-14 events)
+  will not be executed after a user successfully logged in.

typo3/sysext/felogin/Documentation/UsersManual/Index.rst

@@ -43,3 +43,18 @@ for setting this storage folder:
 
    plugin.tx_felogin_login.settings.pages = xxx
 
+
+.. _access-restrictions:
+
+Access restrictions on the felogin plugin
+=========================================
+
+A very common issue is, that the felogin plugin is set to Access:
+:guilabel:`Hide at login`. After the core has processed the login request, the
+page will be rendered without the felogin plugin. If there are redirect options
+active they will **not be executed**, simply because the felogin plugin is
+hidden.
+
+Of course setting the felogin plugin to :guilabel:`Hide at login` and having
+redirect options together doesn't really makes sense.
+