Upon selecting a layer to swipe, these two icons appear, and they are clickable, but clicking them doesn't seem to change the swipe action or results. Documentation doesn't mention these icons either.
1 Answer
They are just standard icons in QGIS' message bar. The first is a countdown timer, showing disappearing ticks until the message automatically disappears. The second indicates the severity of the message. In this case, it's just an information message. If it was a warning or critical error the icon would be different.