All my apps lost their text labels!
I tried rebooting, but it didn't help.
This turned out to be a setting and not an error.
Long-press on the home screen, click on Settings, and then slide "Icon Labels" to ON under both "HOME SCREEN SETTINGS" and "DRAWER SETTINGS". This eliminates the need to clear any cache or data.
Thanks to Rahul for helping me troubleshoot this.
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