While an update operation is proceeding, you can click-and-drag/swipe down to check for updates. This should never be possible while updates are being installed.
Git commit 84f70236f4d98ee53c83ec7fa30a396754e332ad by Aleix Pol. Committed on 16/03/2019 at 20:13. Pushed by apol into branch 'Plasma/5.15'. Don't allow refreshing during updates M +1 -0 discover/qml/UpdatesPage.qml https://commits.kde.org/discover/84f70236f4d98ee53c83ec7fa30a396754e332ad