I wnat to specify the width of the toolbar

Thank you for your attention to this, but your suggestions do not work. Still, the toolbars change width, apparently at random. They also stack onto each other vertically upon reboot or relogon, thus reducing the number of toolbar columns. I have found no way to control how they appear, so I am going to give up on docked toolbars, probably, and use only the standalone ones. But those keep disappearing, as noted in my thread in the bugs section.