[Users] Firefox and Claws Mail

[John Jason Jordan]

Claws Mail 3.9.0 on Fedora 16 x86_64. 

For a long time I have had "Claws-Mail" as the application for Firefox
to use for sending an e-mail when I double-click on a mailto link in a
web page.

It still works, but suddenly now it opens a new instance of Claws Mail
as well as the Compose window. I really don't need this proliferation
of windows. If i close the new instance of Claws Mail it also closes
the Compose window. After composing and sending the message the new
instance of Claws Mail remains active. 

I looked in Claws Mail Preferences to see if there was a "use only one
instance" setting, but there doesn't appear to be such an option. 

Does anyone know a way to make the mailto link open a Compose window
without creating a new instance of Claws Mail as well? Perhaps a change
to the setting in Firefox?