Hi all Anyone else having issues with Mac Mail (OS X El Capitan) crashing when Firefox 43.0 is open? I use Firefox as main browser. Since updating my Mac Mail crashes every time I forward or reply whilst Firefox is open. Have unistalled and reinstalled Firefox. I've tried a SMC and PRAM reset on Mac. I've tried opening a single tab in Firefox. I've tried reducing my home tabs one by one to see if it's one of those that is issue. I've set up a test login on my mac. Looked at plugins but again no major issues. Nothing fixes issue. Definitely only happens when Firefox 42.0 is open. This is a major issue for me as I use online platform (in Firefox) and MacMail for work. Apple support can't help as Firefox is unsupported. Any help much appreciated. Sorry if there is another thread I have missed. Thanks! Susie