Running getGetFeatureInfoUrl() against a TileWms source returns: Either no layer was queryable, or no layers were specified using QUERY_LAYERS
My URL is:
GeoServer docs say: If application/vnd.ogc.gml is supported the request should be successful. All of the layers in question have GML as an available output format in the layer preview options in GeoServer.
OpenLayers docs say: If QUERY_LAYERS is not provided then the layers specified in the LAYERS parameter will be used. LAYERS params is set on all these layers upon configuration.