Column hierarchy breaks when adding new columns after sorting

I have a 3 column table. I want to sort on the 3rd column and then the 1st. I click in the 3rd column and select it. The application indicates that the column I selected is column 1, the first column, not the 3rd. Now I cannot select the 1st column. Clicking in any column gives me a menu that only has the option, "Deselect". This problem arose after I added columns to a table that had an existing, temporary, multicolumn sorting, then resetting the filters, because the new rows were not sorted, and trying to re-establish the previous sort order.

Reproduce the issue in Obsidian by adding columns to an existing table, resetting filters, and rebuilding a multicolumn sort. Trace the sorting state and column-selection handling from the plugin entry points; done means the third column remains identified as column 3 and the first column can be selected afterward.

Written by the indexing model from the issue text.