Compare two lists

Compares two lists line by line and marks the entries that appear in only one of them. Turn on ignore case and ignore whitespace for anything that came out of a spreadsheet.

This is the everyday version of a diff: two exports, two mailing lists, two inventories, and the question is which rows are missing from one side. Two settings matter more here than in a prose diff. Ignore whitespace catches the trailing spaces that spreadsheet exports leave on values, which otherwise make identical entries look different. Ignore case catches email addresses, which are case-insensitive in their domain part and treated inconsistently by most systems. Sorting both lists first makes the result easier to read, since an unsorted comparison marks reordering as change.