Column can be resized unless window size changes

[marcosocamargo]

This is "overflow" mode. Only the last 2 columns are to be resized. The columns cannot be resized unless I changed the browser width like clicking on "Maximize/Restore" which enlarges the window to fill the screen or returns it to its previous size.
I want to resize the columns even when the window size hasn't changed. How do I do that?
Thanks,
-Marcos