string
A string describing how the edges of the panel are linked to the edges of its parent window. Thus when the parent window (which must be a panel or tab window) is resized, the panel can be stretched as a consequence.
The value of panel.linkage is a string similar to a justification string, i.e. L, R, T, B and M. A value of LRTB means that the left, right, top and bottom edges of the sub-panel are linked to the parent, so that when the parent is resized all edges of the sub-panel are redefined maintaining distances from the corresponding parent edges.
A value of M will tie the mid-point of the panel to the mid-point of the parent window resulting in no stretch in the relevant direction (X or Y).
On sub-panel creation if no linkage is specified, the default value "TL" is assumed. This will tie the left and top edges to the parent window but will do no resizing when the parent window is resized.
More complicated linkage requirements should be done via the parent window's window.resize callback.