I noticed that Google Chrome on my wife’s laptop was really old and hadn’t been updated for months. Although a new version appeared in updates and thus rpm-ostree identified there was an updated package, the update was never applied, I always rebooted into an image with the old version.
Today the same happened to my friend with an overlayed MegaSync client.
There were no error messages and the only thing that helped was to uninstall and install the package again.
I wonder if it’s some rare bug or something that has happened to more users and if there is any other solution than just reinstalling the package.