On 5/21/13 9:12 AM, Marta Pawlowska wrote: > Do you know any place/list/ling where such a concept "readonly + > PutForwards" is described? Sure. See http://dev.w3.org/2006/webapi/WebIDL/#PutForwards and http://dev.w3.org/2006/webapi/WebIDL/#dfn-attribute-setter step 3 substep 6. -Boris