Website: Apps with no-icons cause glitches
https://f-droid.org/repository/browse/?fdfilter=firefox&fdid=de.marmaro.krt.ffupdater shows an empty image, because the app doesn't have an icon. I'd recommend having a generic/default icon, as Android itself does.
Searching for Firefox https://f-droid.org/repository/browse/?fdfilter=firefox shows the Fennec icon for FFUpdater (I suspect the last used icon is re-used).
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