src/vs/workbench/services/extensions/common/extensionManifestPropertiesService.ts/ExtensionManifestPropertiesService/getConfiguredExtensionKind
class ExtensionManifestPropertiesService:	private getConfiguredExtensionKind(manifest: IExtensionManifest): (ExtensionKind | '-web')[] | null {
		const extensionIdentifier = { id: getGalleryExtensionId(manifest.publisher, manifest.name) };

		// check in config
		let result: ExtensionKind | ExtensionKind[] | undefined = this.getUserConfiguredExtensionKind(extensionIdentifier);
		if (typeof result !== 'undefined') {
			return this.toArray(result);
		}

		// check product.json
		result = this.getProductExtensionKind(manifest);
		if (typeof result !== 'undefined') {
			return result;
		}

		// check the manifest itself
		result = manifest.extensionKind;
		if (typeof result !== 'undefined') {
			result = this.toArray(result);
			return result.filter(r => ['ui', 'workspace'].includes(r));
		}

		return null;
	}