My display names went missing from Sitecore. But only in my development environment, not the test or production environment.
Some googling lead me to this article from Stackexchange, but my database were in good condition.
It turns out, that even with 15 years of Sitecore experience, I did not know about this feature:
Click the burger menu in the Desktop and select “Application options”:
In the “View” tab, select “Display name (language-specific name)“, and the display names are visible again:
How on earth the setting jumped to “item key”, I simply don’t know.
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