Addons are frequently used in the game and many are accepted by Blizzard. Be sure to use reputable ones. Blizzard suggests that you always use the default launcher to start the program.Many believe that Macs are more secure than PCs. My understanding is that fewer malware programs are created for Max OS's than for Windows, which makes them somewhat less vulnerable to attacks. Whichever the case, Mac users do get attacked, and there is no excuse to be lax with security.