Yeah, that's a bug on our side. We are setting the width of the images there, but not the height. Therefore, some 'long' avatars are showing up a bit wonky.
We're having a v5.1.1 release with some minor bug fixes planned for Friday, and this should be fixed then.
Sorry for the inconvenience and ugliness in the Usermap area for now. Hopefully that's your only issue
Thanks,
Alex