Export Areas fails with no error messages

[ansell]

Describe the bug
Export -> Areas fails silently with no error messages

To Reproduce
Steps to reproduce the behavior:

1. Go to https://spatial.ala.org.au/
2. Open Developer Tools in browser
3. Click on Add to map and then Area
4. Click on Gazetteer polygon and then Next>
5. Type Victorian Midlands and then select the IBRA 7 Regions option and then Next>
6. Click on Export and then Areas
7. Click on any Filetype, as they all silently fail the same way.
8. Click on Next>
9. The dialog closes but nothing happens

Expected behavior
Some form of Shapefile, KML or WKT should be exported.

Actual behavior
It is horribly silently broken.

Screenshots
Not applicable, as there are no visible signs that the application is doing anything in response to the request to export the areas.

Additional context
Firefox 68.0.1 on macOS 10.14.5

References ticket 39604 in helpdesk