@anon87220378
Sorry, It doesn’t look like the link i sent you has any information as some pages in the setup of kmail are non existent! Doesn’t look like they are keeping up with their documentation. Are you trying to use kmail as your email client. It shouldn’t be too hard if you use the built in wizard and it can detect the mail server settings like Thunderbird does.
Don’t know if it’s relevant, but recently an app on my tablet refused to connect properly to gmail (though ti used to work fine). Something that the big "G* has implemented for ‘security’ reasons… App lockout is good for you.
As mentioned, Thunderbird seems unaffected so far. Here’s the TBird settings for GMail…
Site: smtp.gmail.com
Port: 465
SSL/TLS
OAuth2
in case that helps…