I wish to help users to resize their window more easily.
I changed CSS and the json table in dhmlxWindows.js to set width and height of the border to 4px but without success (border still 2px and content size reduced).
Is there something to modify in dhmlxWindows.js?
This is a complex operation - full skin should be rebuilded.
Try to use other skins - there are a lot of skins with more prominent borders.