Copy Style - lifelike/countersheetsextension GitHub Wiki
As a special way of setting the style of something (see Set Style), without having to put the specific SVG values in the CSV (eg typing in the text describing a valid SVG color) it can save a lot of work and be easier to work with just saying use that style taken from this other object over here. This is (currently) only possible for a column with the id[style:part] type of header, and the way to do it is to put <otherid in that column for a counter. That counter will take its style (that part of the style) from the rectangle with id otherid.
Example: If there is a rectangle anywhere in the SVG that has id (set in Object Properties) bkg then in the spreadsheet <bkg in a column to set x[style:fill] the fill for object with id x will be set to the same as the fill for rectangle bkg. This way to modify the fill color of potentially many different counters, and/or many parts of the same counter, it is only necessary to modify the fill of bkg (using the Fill and Stroke Editor in Inkscape) and then generate the countersheet again to give all counters the new color.
Note that before 2.1 this feature was very useful to set up named colors to make the CSV easier to edit (and to be able to modify colors WYSIWYG in the Inkscape user interface rather than putting color-codes in a spreadsheet). With the new support for using Inkscape color Swatches enabled in version 2.1 of the extension it is much more effective to use Swatches for setting up named colors to use.
Some of the things that can be done using this method can in recent versions of Inkscape also be done by using swatches to define colors that can be easily modified to affect many objects in a drawing.
Also see Set Style.