File sizes matter.  I found the function that SMF (what we have) uses when it loads an Avatar and I use the same function.  In the process I discovered that our Avatar settings made Avatars 65 by 65 pixels wide and I changed the setting to 72 x 72.

That made old Avatars lower in resolution so I rebuilt RE's Avatar from an original photo, made is square and gave it a background color.  That was no problem.  Surly1's avatar was also a bit funky from the change so I rebuilt it from the original Banksy photo which is a few thousand pixels wide.  The function choked.

I scaled the image down to 1000 pixels by 1000 pixels, but still had a problem.  500 x 500 worked fine.

It is easy to change the resolution of a photo online.  Find a place and scale the image you like to a 500 x 500 pixel square.  Download it and When you load it up to the forum software it should convert to 72 x 72.

In time I plan on improving photo upload and such.  I only realized I had the skills to customize this place not so long ago.  I had the idea that it was too complicated and avoided the idea.  I was wrong.  Working on my own website gave me the skills.  I was able to add my custom avatar function to a code file that was over 3000 lines long without fucking things up! 

The total length of the code base for this place is between 100,000 and 300,000 lines of code.  Messing with it requires a bit of attention to detail and when I first started I was to too quick to make 'a small change' and loaded up a file without testing it on my local copy of the software first.

We had a 'white screen' for a few hours.  I am more careful now. 

Periodically I back up the website.  I could have it done once a day but that would cost a couple of bucks a month so I just do it when I make a significant change.