Attached Files cannot be previewed in Confluence

Summary

When clicking an attached PDF file from a Confluence page, the inline preview function will not load entirely.

Environment

• Confluence Cloud only

Steps to Reproduce

1. Attach any image/office file
2. click on the File to preview it.

Expected Results

The File is displayed in the browser

Actual Results

The spinner will never complete loading.
The Javascript console will repeatedly throw this error:

Uncaught TypeError: Cannot read property 'length' of null(anonymous function) @ batch.js?highlightactions=true&flavour=VANILLA&analytics-enabled=true&isAdmin=true&locale=en-GB&use…:5807

Fix

We are currently deploying a fixed version of Confluence Previews to all instances. Once the fix is out the inline preview should start working normally once more.