First, I’m an Avast user and not an Avast Team member.
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Em primeiro lugar, sou utilizador do Avast e não membro da equipa do Avast.
You could add an Exception for your mail(.)google(.)com URL (the brackets I have used so the link wouldn’t be active.
That would however leave you potentially at risk from suspect/malicious email.
See attached screenshot this would be what I suggest “mail(.)google(.)com/mail/u/0/” (ignore the brackets in the URL this is just to stop the link being active in the forum).
Now on my Avast Program I don’t have to put Quotes " around the path". The * asterisk is a wildcard for one or more characters you could put that after the mail/ that would stop scanning of all mail folders below that level.
Of course if you don’t want ‘any’ email scanned you could disable the Email Guard.