src/vs/workbench/contrib/notebook/browser/contrib/breakpoints/notebookBreakpoints.ts/NotebookCellPausing/onDidChangeCallStack
class NotebookCellPausing:	private async onDidChangeCallStack(fallBackOnStaleCallstack: boolean): Promise<void> {
		const newPausedCells = new Set<string>();

		for (const session of this._debugService.getModel().getSessions()) {
			for (const thread of session.getAllThreads()) {
				let callStack = thread.getCallStack();
				if (fallBackOnStaleCallstack && !callStack.length) {
					callStack = (thread as Thread).getStaleCallStack();
				}

				callStack.forEach(sf => {
					const parsed = CellUri.parse(sf.source.uri);
					if (parsed) {
						newPausedCells.add(sf.source.uri.toString());
						this.editIsPaused(sf.source.uri, true);
					}
				});
			}
		}

		for (const uri of this._pausedCells) {
			if (!newPausedCells.has(uri)) {
				this.editIsPaused(URI.parse(uri), false);
				this._pausedCells.delete(uri);
			}
		}

		newPausedCells.forEach(cell => this._pausedCells.add(cell));
	}