I can't attach more than 2, or 3 small jpeg photos, to an email without crashing the email.

When I try to attach several (more than three) small email sized jpeg files, my Yahoo email tries to load them, then re-load them, and ultimately gives a splash screen, that says, "Cannot be saved, as a draft", and locks up. The files are 1mb, or less, This was never a problem, before Firefox, and Yahoo issued "new, improved" versions, of their software. If I only attach about three files, at a time, let it attach them, then attach more files, it will attach them with no issue, and I can send the email. This does not seem to be a problem with other browsers.