There should be five lines in the next paragraph ('white-space' is set to 'pre'):
Line Three
There should also be five lines in the next paragraph, even though here 'white-space' is 'normal':
Line Three
If there are only two lines, then "<br>" is being treated specially (e.g., without using generated content).
The next test case has 'white-space' set to 'nowrap':
Line Three
Finally, here 'white-space' is 'normal' everywhere except the generated content, which is set to 'pre':
Line Three
The End.