Created attachment 365782 [details]
Test case to reproduce the issue
Steps to reproduce the problem:
1- Load the attached test case
The word is broken in the last character "D" (actual-result.png)
The word should not be broken (expected-result.png) since available width (4ch) is the same as the word' width
Both Chrome and Firefox render the attached case as described in the expected result.
Created attachment 365783 [details]
Created attachment 365784 [details]
The root cause of this issue might be bug #196353 so I's indeed a good idea to follow what's going on there.