It looks like Tumblr changed some stuff so Profiler weren’t working properly.

I’ve fixed it, and you should get the new version in a few hours.

If you don’t, or if you don’t want to wait:

1. Click on the X icon
2. Click on Manage Extensions, and select Profiler
3. Click Re-install / Manually Update this Extension
4. Refresh the page.

Sorry about that, and thanks for using XKit.