For anyone in the future googling this issue, there is a better answer than my previous one, particularly better than a workarea modification.
To update the display title of a widget in the widget bar:
- Go to Workarea > Settings > Configuration > Personalization > Widgets
- Find your widget in this list and click the edit icon to the left of its name
- Modify the display title in the second text field in the modal that pops up.
Confirmed working in 8.6.1, likely works in all 8+ versions.