Signing UI edge-case cleanup (#6849)

frontend/editor/src/core/components/shared/ShareManagementModal.tsx

@@ -130,7 +130,12 @@ const ShareManagementModal: React.FC<ShareManagementModalProps> = ({
   }, [config?.frontendUrl]);
 
   const loadShareLinks = useCallback(async () => {
-    if (!file.remoteStorageId) return;
+    if (!file.remoteStorageId) {
+      // No remote file yet — clear any leftover state from a previously opened file.
+      setShareLinks([]);
+      setSharedUsers([]);
+      return;
+    }
     setIsLoading(true);
     setErrorMessage(null);
     try {
@@ -161,6 +166,10 @@ const ShareManagementModal: React.FC<ShareManagementModalProps> = ({
 
   useEffect(() => {
     if (opened) {
+      // Clear the previous file's data before loading so a stale list is never
+      // shown (and never targeted by a Remove click) while the new file resolves.
+      setShareLinks([]);
+      setSharedUsers([]);
       loadShareLinks();
       setActivityMap({});
       setShareRole("editor");

frontend/editor/src/core/components/viewer/SignaturePreviewLayer.tsx

@@ -331,6 +331,12 @@ export const SignaturePreviewLayer = memo(function SignaturePreviewLayer({
                             newY = startTop + (startHeight - newHeight);
                           }
 
+                          // Keep the box on-page (mirrors the placement clamp).
+                          newWidth = Math.min(newWidth, 1);
+                          newHeight = Math.min(newHeight, 1);
+                          newX = Math.max(0, Math.min(newX, 1 - newWidth));
+                          newY = Math.max(0, Math.min(newY, 1 - newHeight));
+
                           onChange(
                             previews.map((p) =>
                               p.id === preview.id