Both of your solutions pass without problems so I'll close this issue.

yes very sure. i did a manual substring on the last line to limit it to 11 characters. also i print the output and can confirm that it has only the expected length 11, so the test is not referring to the last line. also in the other tests you can see they are checking line by line, after "sit amet," comes "consectetur", which has exactly 11 characters. however since this is in the middle of the text, it has to be justified to length 20. maybe there is a non-mentioned rule, that if only one word fits into a line, no gaps should be added? okay i think this has to be the answer.. just read the last line of the description:
"Strings with one word do not need gaps ('somelongword\n')." I cannot test it right now, but i am pretty sure this is it.

having the same or a very similar issue:
Testing length of line 20
Test Passed: Value != undefined
Test Passed: Value == string
Test Passed: Value != 0
Test Passed: Value == 44
Test Passed: Value == 20
Test Passed: Value == Lorem ipsum dolor
Test Passed: Value == 20
Test Passed: Value == sit amet,
Line length is not equal 11 - Expected: 11, instead got: 20

The line length is set to 20, so since this is not the last line, it should have length 20 as it does. Why does the test expect length 11?