Issue Summary

On browsers where cache is disabled, users can encounter inoperative mentions and comment creation. 

This is reproducible on Data Center: yes

Steps to Reproduce

The issue can't be consistently reproduced. However, we've been able to reproduce it by doing the following:

1. Navigate to an issue view page, or go to Issues>Search for Issues (detail view)
2. Launch the Chrome Dev Tools (right-click > inspect element)
3. Switch to the Network tab and check disable cache, select Fast /Good 3G as bandwidth limit (throttling)
4. Switch to the Console and type wiki-edit in filter to catch the error.
5. Hard-refresh the page (ctrl [Windows] / cmd [Mac] + shift + r)
6. Click the pencil icon next to the description box.
7. Repeat steps 4 and 5 until the bug occurs (every time the error is shown in the Console tab).

Expected Results

The rich text editor loads with the existing content and is editable.

Actual Results

The rich text editor opens, but existing content is missing. The text insertion cursor does not appear while hovering over the body. The controls (style, bold, italics, etc.) are greyed out and show a loading icon when hovering.

The below exception is thrown in the browser's console:

Error: jira/mention/mention missing wiki-edit/api

Workaround

Make sure that your browser cache is not disabled and bandwidth limited. Refreshing the page should resolve the issue.

Additionally, monitor network bandwidth and check if the problem is generated when the speed slows down.