Save position of panel-divider for custom columns

[Sombra]

Several suggestions for improve visualization of custom columns were raised at this forum (allow more than 29 custom columns, allow save to files the schemas, etc.) but I didn't see about save position of divider.
My suggestion is for add an option with a checkbox in edit custom columns dialog.
For example: [x] Save position of window divider"

IMHO this will help to show correctly some custom columns in which is necessary a bit more of space in panel for show ALL columns.