src/vs/workbench/contrib/debug/browser/callStackView.ts/CallStackAccessibilityProvider/getAriaLabel
class CallStackAccessibilityProvider:	getAriaLabel(element: CallStackItem): string {
		if (element instanceof Thread) {
			return localize({ key: 'threadAriaLabel', comment: ['Placeholders stand for the thread name and the thread state.For example "Thread 1" and "Stopped'] }, "Thread {0} {1}", element.name, element.stateLabel);
		}
		if (element instanceof StackFrame) {
			return localize('stackFrameAriaLabel', "Stack Frame {0}, line {1}, {2}", element.name, element.range.startLineNumber, getSpecificSourceName(element));
		}
		if (isDebugSession(element)) {
			const thread = element.getAllThreads().find(t => t.stopped);
			const state = thread ? thread.stateLabel : localize({ key: 'running', comment: ['indicates state'] }, "Running");
			return localize({ key: 'sessionLabel', comment: ['Placeholders stand for the session name and the session state. For example "Launch Program" and "Running"'] }, "Session {0} {1}", element.getLabel(), state);
		}
		if (typeof element === 'string') {
			return element;
		}
		if (element instanceof Array) {
			return localize('showMoreStackFrames', "Show {0} More Stack Frames", element.length);
		}

		// element instanceof ThreadAndSessionIds
		return LoadMoreRenderer.LABEL;
	}