[TYPO3-english] sr_feuser_register dependencies, Typo3 4.5.39, e.g. felogin

[rsbrux]

The Status Report for the Typo3 4.5.39 installation which I am attempting to maintain complains that sr_feuser_register 2.6.1 is insecure.
Under "Check for Extension Updates", I find sr_feuser_register 3.1.3, which appears to be compatible with Typo3 4.5.x.
However, I cannot install it, because "The running version of extension "felogin" (1.3.1) is lower than required (4.5.0)."
When I search for a newer version of felogin, I cannot find one.
I have looked in the Typo3 backend under:
"Check for Extension Updates"
"Extension Manager"
"Import Extensions"
and
"Install Extensions"
A web search turns up the Wiki page:
http://wiki.typo3.org/Felogin
and other extension pages, such as:
http://typo3.org/extensions/repository/view/changepassword
refer to felogin, but the referenced Extensions page:
http://typo3.org/extensions/repository/view/felogin
says
"Extension not found"
Even a repository search with the "Show outdated extensions" option:
http://typo3.org/extensions/repository/?id=23&L=0&q=Felogin&tx_solr%5Bfilter%5D%5Boutdated%5D=outdated%3AshowOutdated
doesn't find anything, not even the currently installed version, 1.3.1
What has happened to the felogin extension?
How can I bring my website up to date and close the security holes?

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