Do not update time if top grid is invisible

src/revealers.js

@@ -182,7 +182,7 @@ class ClapperRevealerTop extends CustomRevealer
             : Gtk.RevealerTransitionType.CROSSFADE;
 
         /* Changing transition in middle can have dire consequences,
-           so change only when not in transition */
+         * so change only when not in transition */
         if(this.reveal_child === this.child_revealed)
             this.transition_type = this._requestedTransition;
     }

src/widget.js

@@ -333,7 +333,10 @@ class ClapperWidget extends Gtk.Grid
 
     updateTime()
     {
-        if(!this.revealerTop.visible)
+        if(
+            !this.revealerTop.visible
+            || !this.revealerTop.revealerGrid.visible
+        )
             return null;
 
         const currTime = GLib.DateTime.new_now_local();