Cannot place cursor after User Mention

Summary

When adding an @mention to a Confluence page and save the page, the cursor is placed at the beginning of the username so no text can be appended.

Environment

• Safari 11.0.3
• Confluence 6.10.1

Steps to Reproduce

1. Create a page
2. Add an @mention and click “Return”
3. Publish the page
4. Edit the page
5. Put the cursor at the end of the @mention

Expected Results

The cursor remains at the end of the mention.

Actual Results

The cursor is placed in front of the username as shown below:

No text can be added on that line following the @mention

Workaround

This is not occurring in Firefox or Chrome, so you can use either browsers as a workaround.