How to sort a list by first non-modifier character?

[tiffle]

Really? - check this out:

@peternlewis

OK, so you are wanting the blank lines in the middle removed, which is not what the Trim Whitespace does (it removes white space from either end of the string.

Use a Search and Replace action, with regex \R+ and replace \n and that will replace any sequence of one or more line endings with a single linefeed.