🐛 Fix update library dialog when a component position changes

Do not show the library sync popup when the only differences are global x/y changes on library components. We now generate the actual sync changes and only notify if there are real redo-changes to apply.
Run cll/generate-sync-file-changes for candidate libraries and filter out those with empty :redo-changes. The expensive check is deferred via rx/timer 0 so it runs asynchronously and does not block the UI.
Why: Position-only changes are normalized during sync (via reposition-shape) and never propagate to copies; showing the popup in that case was a false positive.
Performance: The check is deferred to the next tick to avoid UI stutter on large files with many libraries.

CHANGES.md

@@ -26,6 +26,7 @@
 - Fix lost-update race on `team.features` during concurrent file creation (by @web-dev0521) [Github #9197](https://github.com/penpot/penpot/issues/9197)
 - Fix copy and paste actions crashing the workspace on insecure origins (plain HTTP / non-`localhost`) where the Clipboard API is unavailable (by @MilosM348) [Github #6514](https://github.com/penpot/penpot/issues/6514)
 - Fix blend-mode dropdown leaving the canvas rendered with the last hover-preview blend mode when dismissed without selecting an option; the WASM render is now reverted to the saved blend mode on pointer-leave (by @edwin-rivera-dev) [Github #XXXX](https://github.com/penpot/penpot/issues/XXXX)
+- Fix update library dialog when a component position changes [Taiga #11981](https://tree.taiga.io/project/penpot/issue/11981)
 
 ## 2.16.0 (Unreleased)
 

frontend/src/app/main/data/workspace/libraries.cljs

@@ -1281,38 +1281,61 @@
             file         (dsh/lookup-file state file-id)
             file-data    (get file :data)
             ignore-until (get file :ignore-sync-until)
-            permissions (:permissions state)
+            permissions  (:permissions state)
 
             libraries-need-sync
             (->> (vals (get state :files))
                  (filter #(= (:library-of %) file-id))
-                 (filter #(seq (assets-need-sync % file-data ignore-until))))
+                 (filter #(seq (assets-need-sync % file-data ignore-until))))]
 
-            do-more-info
-            #(modal/show! :libraries-dialog {:starting-tab "updates" :file-id file-id})
+        (if-not (and (:can-edit permissions)
+                     (seq libraries-need-sync))
+          ;; Fast path: no libraries need sync based on timestamps
+          (rx/empty)
 
-            do-update
-            #(do (apply st/emit! (map (fn [library]
-                                        (sync-file (:current-file-id state)
-                                                   (:id library)))
-                                      libraries-need-sync))
-                 (st/emit! (ntf/hide)))
+          ;; Defer the expensive change generation check to avoid blocking the UI.
+          ;; For files with many libraries, this prevents stuttering/freezing.
+          (->> (rx/timer 0)
+               (rx/map (fn [_]
+                         ;; This runs asynchronously on the next tick.
+                         ;; Filter libraries to only those that would produce actual sync changes.
+                         (let [libraries (dsh/lookup-libraries state)]
+                           (filter (fn [library]
+                                     (seq (:redo-changes
+                                           (cll/generate-sync-file-changes
+                                            (pcb/empty-changes)
+                                            nil
+                                            nil
+                                            file-id
+                                            nil
+                                            (:id library)
+                                            libraries
+                                            file-id))))
+                                   libraries-need-sync))))
+               (rx/filter seq)
+               (rx/map (fn [libraries-with-changes]
+                         (let [do-more-info
+                               #(modal/show! :libraries-dialog {:starting-tab "updates" :file-id file-id})
 
-            do-dismiss
-            #(st/emit! ignore-sync (ntf/hide))]
+                               do-update
+                               #(do (apply st/emit! (map (fn [library]
+                                                           (sync-file file-id (:id library)))
+                                                         libraries-with-changes))
+                                    (st/emit! (ntf/hide)))
 
-        (when (and (:can-edit permissions)
-                   (seq libraries-need-sync))
-          (rx/of (ntf/dialog
-                  :content (tr "workspace.updates.there-are-updates")
-                  :controls :inline-actions
-                  :links   [{:label (tr "workspace.updates.more-info")
-                             :callback do-more-info}]
-                  :cancel {:label (tr "workspace.updates.dismiss")
-                           :callback do-dismiss}
-                  :accept {:label (tr "workspace.updates.update")
-                           :callback do-update}
-                  :tag :sync-dialog)))))))
+                               do-dismiss
+                               #(st/emit! ignore-sync (ntf/hide))]
+
+                           (ntf/dialog
+                            :content (tr "workspace.updates.there-are-updates")
+                            :controls :inline-actions
+                            :links   [{:label (tr "workspace.updates.more-info")
+                                       :callback do-more-info}]
+                            :cancel {:label (tr "workspace.updates.dismiss")
+                                     :callback do-dismiss}
+                            :accept {:label (tr "workspace.updates.update")
+                                     :callback do-update}
+                            :tag :sync-dialog))))))))))
 
 (defn touch-component
   "Update the modified-at attribute of the component to now"