src/vs/workbench/contrib/welcome/walkThrough/browser/walkThroughPart.ts/WalkThroughPart/addFrom
class WalkThroughPart:	private addFrom(uri: URI) {
		if (uri.scheme !== 'command' || !(this.input instanceof WalkThroughInput)) {
			return uri;
		}
		const query = uri.query ? JSON.parse(uri.query) : {};
		query.from = this.input.getTelemetryFrom();
		return uri.with({ query: JSON.stringify(query) });
	}