javascript - Debugging sourcmaps in Chrome -

i'm having trouble getting chrome use indexed source map uses 'url' fields in 'sections' array.

according does chrome support multiple modules/sourcemappingurls on single javascript url, seem supported, can't seem work.
can see chrome fetching source map, doesn't fetch of urls pointed in source map.

are there debugging tools available try , figure out problem is. generating invalid json source map chrome didn't complain or output errors or warnings console.

is there place else in chrome can errors related parsing or processing source maps?

here's source map:

{     "version" : 3,     "file" : "app.js",     "sections" : [         {"offest" : {"line":17, "column":89}, "url":"./_sourcemap/dojo/cldr/nls/en/gregorian.map"},         {"offest" : {"line":22, "column":555}, "url":"./_sourcemap/dijit/calendar.map"},         {"offest" : {"line":30, "column":66}, "url":"./_sourcemap/dojo/date.map"},         {"offest" : {"line":34, "column":213}, "url":"./_sourcemap/dojo/date/locale.map"},         {"offest" : {"line":47, "column":301}, "url":"./_sourcemap/dojo/cldr/supplemental.map"},         {"offest" : {"line":49, "column":139}, "url":"./_sourcemap/dojo/cldr/nls/gregorian.map"},         {"offest" : {"line":58, "column":470}, "url":"./_sourcemap/dijit/calendarlite.map"},         {"offest" : {"line":70, "column":1965}, "url":"./_sourcemap/dijit/form/dropdownbutton.map"}     ] }