Just to be clear.
With this change, we allow for comparison of columns with implicit names, however, we do not support implicit column names in the include/exclude filters.
Is that right?

That's correct, I have tested filters and problem is that there is no clear distinct between a column name in filter or xpath expression. E. G. ('Test', '\/test') without knowing these we would ass that second value is a special name for column where in fact was invalid xpath.

Can you add a note to advanced_data_comparison.md to inform that exclude/include does not support columns with implicit names?
We could also add a test to prove that it's not working - as an expected behavior.

The test should document, what happens today if we use the exclude() with implicit column name.

Of course 👍