alt tabbing by accident to a folder full of goat pr0n thumbnails = quite routine in schools/during presentations

It's not 100% unless you're using an input to record audio and then it's there for a reason. 99% of the people in these threads aren't going to see this during their PowerPoints because they're not recording anything and the 1% that do and care about the dot should be using a hardware I/O device anyways because the OS can do a lot more than just display a dot. Additionally, applications can also fix this themselves by using Apple's APIs.