Issue Summary

The Summary field accepts a new line character (\n) if the second line doesn't have any other character.

Steps to Reproduce

1. Go to a spreadsheet app (like Google Sheets or Numbers)
2. Copy two cells, one with text and a blank cell below
3. Edit the Summary of a ticket and paste the copied text
4. Save.

Expected Results

The field will not accept the entry.

Actual Results

If nothing else is entered after the new line character, the Summary field is saved successfully. Editing the field again confirms that the line break character is retained.

If another character is entered in the new line, the error "We couldn't update the summary" appears.

Note that this doesn't happen in Jira Software projects, where the message "New lines are not allowed in summary" appears when trying to save.

Impact

Even though the new line is omitted in the UI, integrations, notifications, and third-party apps may not work as expected when this new line character is present.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available