Trying to install/run Firefox on new iMac. Downloaded the most recent version. Clicked on installer icon. Dragged the icon to app folder. Seemed to install. Ejected installer. App folder shows only a 2k alias,,,no "program". Click app icon. Installation icon reappears on desktop and process starts all over again!!! On old iMac the app shows as a 375Mb application! Any help would be appreciated as I have no hair left to pull out. PS: the iMac won't let Chrome run either. Says it can't be opened because Apple can't check for malicious software, even though install process verified the disk image!!!