When creating new Issues in the Backlog/Development Panel, I type a summary in the 'What needs to be done?' dialog box and hit enter.  After that, a window pops up to create a new Issue with an error message at the top that says:

'Unfortunately, there is an internal communication error, so you must use the full dialog to create the issue. Please contact your administrator if this error keeps appearing.'

I fill out the summary to create the same Issue, but the original Issue is still generated, leaving me with 2 Issues with the same title.