If I'm following the various tickets on this correctly this is still open:
https://github.com/umbraco/Umbraco-CMS/pull/16049
Though this ticket says a fix was merged into 13.4
I can't see anything working - steps to reproduce.
Copy a deep linked url in Umbraco (e.g. whilst viewing a node where the url shows the node ID).
Log out - hit that url. You get the Umbraco login screen but on success you just hit the root content page.