This bug happened to me very rarely (once every 5 or 6 years?), but, for me, being forced to read with crippled fonts in the browser is a big pain in the back
So this is a quick and dirty explanation of how to fix:
in case someone is wondering why, from time to time, on a linux server the command
sudo su -
seems stuck or just much slower than normal in starting.. this may be because when the command
sudo su -
is starting, by default it scans wtmp to report last login time from user root and, if on such servers there are hundreds of users, last root access entry may be deep in the access list
the quick trick I have found to fix it is to launch first a simple
sudo bash
(so a new entry for root is reported at the top of wtmp) and then closing it at once - after that any next
sudo su -
returns to be as fast as usual