Column problem in TSV mode

I have a tab separated file (Windows ASCII) where column 1 contains data mostly less than 100 chars, but occasional entries up to 290 chars. Columns 2 and 3 contain values less than 10 chars.

After loading, the screen is correctly formatted in TSV mode. As I want to see what’s in column 1 I go to the ruler and drag the column 1 boundary to the left by 20 (or more) chars.

If I have a long entry in column one, the values in columns 2 and 3 sit on top of the column 1 data, but if there are any padding spaces in columns 2 and 3, the character values from column 1 underneath show through. If I then scroll the file window to left or right and then scroll back (causing the window to repaint) the values in columns 2 and 3 disappear and the value in column 1 extends across columns 2 and 3.

At all times the grey vertical line defining the column boundary works correctly.

As I’ve manually dragged column 2 on top of column 1 I’d expect to see column 2 data without any bleed through and the column 1 data to ‘disappear’ until I extend column 1 again. Naturally this is just a visual formatting issue as the underlying data will not have changed.

This behavior has been observed in 10.0.1 and 10.0.5

I’ve not had a chance to see if this happens in CSV or other modes.

Cheers