update

frontend/src/components/ParticipantSelector.tsx

@@ -145,6 +145,20 @@ export const ParticipantSelector = ({
           className="flex-1 min-w-[100px] h-7 border-none shadow-none focus-visible:ring-0 p-0 text-sm bg-transparent placeholder:text-muted-foreground/70"
         />
 
+        {isDropdownOpen && (
+          <button
+            onClick={(e) => {
+              e.stopPropagation();
+              setIsDropdownOpen(false);
+              inputRef.current?.blur();
+            }}
+            className="p-1 hover:bg-muted rounded-full transition-colors ml-1"
+            title="Close"
+          >
+            <X className="w-4 h-4 text-muted-foreground" />
+          </button>
+        )}
+
         {isDropdownOpen && filteredParticipants.length > 0 && (
           <div className="absolute top-full left-0 z-50 w-full mt-2 bg-popover border border-border rounded-lg shadow-popover animate-scale-in overflow-hidden">
             {filteredParticipants.map((participant, index) => (