Version: 54.0.2816.0
OS: iOS 9.3 (iPhone SE)

What steps will reproduce the problem?
(1) Visit badssl.com and click on "longextendedsubdomainnamewithoutdashesinordertotestwordwrapping"

What is the expected output?
The page shows "longextendedsubdomainnamewithoutdashesinordertotestwordwrapping.badssl.com" on one line, vertically centered.

What do you see instead?
The page shows *three* copies of the line. One is where it should be, two are below. (portrait.png)
If I change to landscape, I see two copies of the line. (landscape.png)

I don't even know what this falls under, or if it's WebKit's fault. stuartmorgan@, could you triage?