Thanks. But this solution only affects visual admin. Anyone with access to DDBB can still see the password in plain text, which is a huge security hole nowadays with wordpress.
As a good (and recent) example, check how the hackers in the infamous #Panamapapers leack, accesed the email server. They got the DDBB access through an outdated revslider plugin. Then, a smtp plugin (not this one, but similar) that also stored the password in plain text, gave them access to the email servers... :(
https://www.wordfence.com/blog/2016/04/panama-papers-wordpress-email-connection