After setting up a custom column width by dragging the vertical column divider line left or right in the editor, the resulting HTML has a max-width: 320px no matter what the column width is. This is after starting from the two-column 33%/67% column layout and then adjusting it manually.

This can result in conflicting css properties such as:

min-width: 768px;

max-width: 320px;

Some html renderers seem to still work with that, but the IronPDF renderer doesn't know what to do with that and shows the columns both at 50%.