What version are you running?
1.6.1
What's the URL of the page containing the problem?
https://reviewboard.dev.icw.int/users/<userid>/
What steps will reproduce the problem?
1. Set up an avatar at gravatar.com based on a PNG (instead of a JPEG)
2. Navigate to https://reviewboard.dev.icw.int/users/<userid>/
3. The avatar will not show up, but the generic Gravatar logo is shown instead
What is the expected output? What do you see instead?
What operating system are you using? What browser?
Please provide any additional information below.
AFAICS, Review Board uses URLs like this: http://www.gravatar.com/avatar/c9c255632e37104c6f9613a44d55e89f.jpg?s=175
These hardcode a file type preference. After dropping the .jpg extension, PNG Gravatars are also resolved correctly:
http://www.gravatar.com/avatar/c9c255632e37104c6f9613a44d55e89f?s=175
