I'm using TB-9 / WebMail 1.4.6 / WebMail - Yahoo 1.5.6 and experiencing intermittent
server error 500 on the first "Get Mail" attempt only.
"My settings obtained from Webmail add-on help sources/forums"
[Options >> Security >> Web Content]
Accept cookies from sites - unchecked (no check.mark)
[Options >> Advanced >> Config Editor]
network.cookie.cookieBehavior - 2
network.cookie.alwaysAcceptSessionCookies - true
Add-on options [WebMail-Yahoo >> Options >> Advanced]
Use Short ID - check.marked
Reuse http session data - check.marked
Compacting folders; http://kb.mozillazine.org/Compacting_folders (not
compacting (clean-up) folders may cause problems).
