I followed a link to an issue which had a trailing comma after the issue key in the URL. It displayed with no indication that there was a problem. On trying to add a comment, I got the Communications Breakdown error ("The JIRA server could not be contacted.").

While this is clearly an edge case, it happened on a link that was detected in text, with the following comma being included in the URL.

Steps to Reproduce:
1. Open a issue and add "," (comma) to the end of the url. This could happen when user click on a link in a chatroom.
2. Add a comment to the issue.

Expected Result:
Some earlier indication that there's a problem, or for all operations to work. An upfront 404, redirection to the correct URL or for commenting to work.

Actual Result:
Got the Communications Breakdown error ("The JIRA server could not be contacted.").