"Stop Timer Automatically" Feature Not Working

* **OS version**: macOS 10.15.3
* **Browser version**: Chrome Latest Stable 
* **Extension version**: 1.60.5

### 🐛 Describe the bug

When using the "Stop Timer Automatically" feature, the timer will not stop when the browser is closed.  

### Expected behaviour

When the browser is closed, the timer should automatically stop. 


### Other details or context

N/A