# Breaking on exceptions

To instruct the debugger to pause on an [exception](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error), tick these checkboxes in the {ref}`Breakpoints list <debugger-ui-tour-breakpoints-list>`:

- Pause on exceptions
- Pause on caught exceptions

```{image} version64ui.png
:alt: Screen shot showing "Pause on exceptions
:class: center
```

When an exception occurs, the line where it occurs is highlighted in the source pane, with a squiggly red line under the problematic code. A tooltip describes the exception. A disclosure triangle within the tooltip reveals a stack trace.

```{image} exception-tooltip-stacktrace.png
:alt: Screenshot of a tooltip for an exception
:class: center
```