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Enhance GMail Basic HTML with keyboard shortcuts
A simple script that adds keyboard shortcuts to the HTML-only version of Gmail: https://mail.google.com/mail/u/0/h/
gi Go to inbox
gk Go to first label inbox
t Toggle checkbox of current mail
mr Mark checked mails as read
mu Mark checked mails as unread
k Navigate up in mail list (shift twice as fast)
j Navigate down in mail list
h Go to older mail(s)
l Go to newer mail(s)
Enter Open mail
r Reload
b Back
n New mail