this update renamed the app's launcher id (from fluxer to app.fluxer.FluxerDesktop) as part of the new Linux global shortcuts work, so existing pins break once. unpin the old icon and pin Fluxer again from the app menu and it should stick across future updates. if you installed the AppImage with Gear Lever or AppImageLauncher, re-integrating it once picks up the new id.
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Comment by Hampus