Steps to reproduce the problem:
1. Open the jsbin test page
2. View the end result in FF/IE and compare with Chrome
What is the expected behavior?
The first BFC in this item should grow to the height of its contents.
What went wrong?
For some reason the calculation is incorrect. Interestingly, if you uncomment the line that sets the float's height to 106px instead of 105 it renders the same as FF/IE.
Thanks for the report, Greg!