Bugfix: FSS Basic List and FSS Extended List print comment at the start of the Content.

Bugfix: FSS Basic List and FSS Extended List print comment at the start of the Content.

When the Content exists at the start of the Content, the comment character ('#') is printed when it should not be printed.

This is a bug where the code initializes the newline_last at the range.start.
The code logic then always expects the newline_last to represent an actual new line.
This is not necessarily the case for when newline_last is pointing to the initial range.start position.

Add a check when processing a comment to ensure that the newline_last is in fact a new line.