I viewed all boards.
I went to copy an existing board and I selected scrum board.
When I clicked the into the name field I got this error beofre I could start typing.
I would start by looking through the JIRA log files to see if any error gets thrown during this operation. When I have encountered this in the past, it usually had something to do with data inconsistency and the index becoming impacted as a result.
See here for some potentially related documentation:
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