This code has no effect in Firefox, Chromium, Windows Mobile Edge and probably many other modern browsers, so this code may be simply forgotten behind.
You may actually only be able to witness that
focus() thing if you use Opera presto and open link in background tab (my case and it’s bothering that tabs opened in the background, suddenly steal the focus and are brought to the foreground).
The fact that this code does not work in most common browsers makes it quite like dead code.
Could it be removed, sooner or later?
With kind regards.