src/vs/workbench/services/extensions/common/abstractExtensionService.ts/AbstractExtensionService/_startExtensionHosts
class AbstractExtensionService:	private _startExtensionHosts(isInitialStart: boolean, initialActivationEvents: string[]): void {
		const extensionHosts = this._createExtensionHosts(isInitialStart);
		extensionHosts.forEach((extensionHost) => {
			const processManager = this._instantiationService.createInstance(ExtensionHostManager, extensionHost, initialActivationEvents);
			processManager.onDidExit(([code, signal]) => this._onExtensionHostCrashOrExit(processManager, code, signal));
			processManager.onDidChangeResponsiveState((responsiveState) => { this._onDidChangeResponsiveChange.fire({ isResponsive: responsiveState === ResponsiveState.Responsive }); });
			this._extensionHostManagers.push(processManager);
		});
	}