Issue Summary

This is reproducible on Data Center: (yes)

Steps to Reproduce

1. Visit any issue in a JSM project 
2. Begin writing a comment
3. Be in Visual Mode
4. Write some content into the comment box
5. Click the canned responses menu item to dropdown available canned responses
6. Do not select a canned responses and do not click away from the dropdown. With the dropdown menu left open, switch to Text Mode

Expected Results

Whatever you had written while in Visual Mode will be retained in Text Mode.

Actual Results

The contents of the comment will disappear completely and looks to be unrecoverable.

Workaround

No known workaround at this time.