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Using a indexed source map like the kind described in https://github.com/mozilla/source-map/blob/7a263408de1b60e60b6220ca3e36d9b3e4aa047d/lib/source-map-consumer.js#L673-L722 or those produced by the closure-compiler when producing bundled output the JS debugger fails to parse the sourcemap.

https://sourcemaps.info/spec.html#h.535es3xeprgt is the spec for indexed bundles.

When you try to use one of these, this assert will be tripped up: https://github.com/microsoft/vscode-js-debug/blob/main/src/common/sourceMaps/sourceMapFactory.ts#L81 due to the not checking for sections data.

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These types of source maps should be supported.