This add-on function receives the width and height of the browser. These values can then be bound to the spreadsheet and in turn the width and height of the main canvas can be bound to these values. This will allow your project canvas to change size as the browser size changes.
You can also use these values to dynamically size and position onscreen components by calculating size and positions in the spreadsheet and binding the respective properties of your onscreen components to those cells.
See the attached video for an example.
Please note that this add-on function currently works for Squirrel Cloud publishing not Squirrel Local. This may be enhanced in the near future depending on the communities appetite for this type of functionality.