1. Currently, when you right-click (or two-finger tap on the trackpad) anywhere in the register column heading bar, you get a pop-up list of columns to show/hide. How about this: when the mouse pointer changes to the width-slider, and you right-click, you would get a pop-up box to specify that column's width - best unit of measure would probably be pixels, because screen sizes and resolutions vary.
2. Also in that pop-up column-width box, have options to "copy all columns and widths" and "paste copied columns and widths." Then, you could copy columns and widths, go to another account's register, right-click on a header-bar width-slider, and paste the copied columns and widths. If you copied a different register's columns and widths, the old copied ones would be overwritten in the paste buffer.
3. The super-deluxe version of this idea would be for the pop-up column-width box to have the option to "use columns and widths from: [Account 1's Name] [Account 2's Name] [etc.]"
But the precision-width feature in #1 is the most important. This would eliminate the maddeningly tedious process of dragging column widths pixel-by-pixel in multiple registers. (I've got 19.)
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