Issue Summary

Jira pages stopped displaying in Firefox.
Sidebar on Issue view screen and Agile boards are not loading.
Only the top of the page is displayed for individual issues.

Steps to Reproduce

1. Open Issue view or any Agile boards on Firefox

Expected Results

Pages load and render all the components

Actual Results

Sidebar on Issue view screen and Agile boards are not loading. 

Health Check is also not loading.

Workaround

Clear cookies & site data via the site information link (padlock on the left-hand side of location bar).
Use other browsers.