I went to convert a lead into a account. But, the options to do this, I am no longer sure where it is. I recall using it because recently upgrading to v8 of suitecrm.
I can change the status button to converted, but this does not put be through the process of creating a new account, and converting the lead into a contact.
It’s not a bug. Brand new install, it works fine.
I’d suggest the following:
reset permissions
clear your cache
In my post you linked about the lead button missing, try replacing that file I highlighted with a fresh copy (and make sure the permissions are correct)