If for a given filed wiki renderer is enabled e.g. Comments, jira.projectkey.pattern in jira-application.properties is configured in the following way:

jira.projectkey.pattern = (([A-Z]|[0-9])

)

and a user enters into the filed a string that contains the dash character for e.g.

the character before dash is duplicated when filed is previewed or sent to JIRA for e.g.