First email client was outlook express, than thunderbird, than gmail. I tried mutt, i tried others. I'm not syncing my mails anymore i just get an pop up from

First email client was outlook express, than thunderbird, than gmail. I tried mutt, i tried others. I'm not syncing my mails anymore i just get an pop up from my webbrowser that a new email is here. I also use different computers (home desktop, home laptop, work desktop) and prefer the same ui with the same settings on all pcs. The browser became in some way, my operating system for mails.