Hi, this happens on Chrome but not on Firefox nor Edge. When there are many columns, and if Chrome's tab is zoomed in, the first column header's right border can be grabbed and dragged to change the column's width, but this grab point starts to deviate from the border line more and more as the later columns are tried. This problem is not noticeable with a few columns, but with about 30 columns over maybe 3000 pixels for example, the gap becomes quite big in the rightmost column. I use pro 3.4.0.