Somehow, I found out how to upload my own picture for my profile on Khan Academy. However, this only works for community posts. It won't work on actual comments for an article or a video. All you have to do is go on your help center, and click on your username and press My profile. Then, press edit profile and upload your profile photo. It truly does save onto your profile for community posts. If you don't believe me, then just look at my profile picture.

From,

Apple12