mailto: links check a preference network.protocol-handler.external.mailto and if that is true then mailto: links will always launch the external mailer, even if Mail is installed. However File/New/Message and File/Send Link only check to see if Mail is installed in which case they will never launch an external mailer. One way of determining whether mailto: links will launch the external mailer is to get the IO service, then use if (ioService.getProtocolHandler("mailto") instanceof Components.interfaces.nsIExternalProtocolHandler) ...
Silly me :-[ *** This bug has been marked as a duplicate of 152526 ***
Status: NEW → RESOLVED
Last Resolved: 14 years ago
Resolution: --- → DUPLICATE
Status: RESOLVED → VERIFIED
QA Contact: benc
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