fix: Improve Core Data thread safety and resolve scrolling flicker

- Add background context support to CoreDataManager
- Fix TagEntity threading crashes in LabelsRepository
- Prevent WebView height updates during scrolling to reduce flicker
- Add App Store download link to README

README.md

@@ -18,9 +18,15 @@ https://codeberg.org/readeck/readeck
   <img src="screenshots/ipad.webp" height="400" alt="iPad View">
 </p>
 
-## TestFlight Beta Access
+## Download
 
-You can now join the public TestFlight beta for the Readeck iOS app:
+### App Store (Stable Releases)
+The official app is available on the App Store with stable, tested releases:
+
+[Download Readeck on the App Store](https://apps.apple.com/de/app/readeck/id6748764703)
+
+### TestFlight Beta Access (Early Releases)
+For early access to new features and beta versions (use with caution):
 
 [Join the Readeck Beta on TestFlight](https://testflight.apple.com/join/cV55mKsR)
 

readeck/Data/CoreData/CoreDataManager.swift

@@ -50,6 +50,16 @@ class CoreDataManager {
         return persistentContainer.viewContext
     }
     
+    var mainContext: NSManagedObjectContext {
+        return persistentContainer.viewContext
+    }
+    
+    func newBackgroundContext() -> NSManagedObjectContext {
+        let context = persistentContainer.newBackgroundContext()
+        context.automaticallyMergesChangesFromParent = true
+        return context
+    }
+    
     func save() {
         if context.hasChanges {
             do {

readeck/Data/Repository/LabelsRepository.swift

@@ -1,7 +1,7 @@
 import Foundation
 import CoreData
 
-class LabelsRepository: PLabelsRepository {
+class LabelsRepository: PLabelsRepository, @unchecked Sendable {
     private let api: PAPI
     
     private let coreDataManager = CoreDataManager.shared
@@ -17,27 +17,28 @@ class LabelsRepository: PLabelsRepository {
     }
     
     func saveLabels(_ dtos: [BookmarkLabelDto]) async throws {
-        for dto in dtos {
-            if !tagExists(name: dto.name) {
-                dto.toEntity(context: coreDataManager.context)
+        let backgroundContext = coreDataManager.newBackgroundContext()
+        
+        try await backgroundContext.perform { [weak self] in
+            guard let self = self else { return }
+            for dto in dtos {
+                if !self.tagExists(name: dto.name, in: backgroundContext) {
+                    dto.toEntity(context: backgroundContext)
+                }
             }
+            try backgroundContext.save()
         }
-        try coreDataManager.context.save()
     }
     
-    private func tagExists(name: String) -> Bool {
+    private func tagExists(name: String, in context: NSManagedObjectContext) -> Bool {
         let fetchRequest: NSFetchRequest<TagEntity> = TagEntity.fetchRequest()
         fetchRequest.predicate = NSPredicate(format: "name == %@", name)
         
-        var exists = false
-        coreDataManager.context.performAndWait {
-            do {
-                let results = try coreDataManager.context.fetch(fetchRequest)
-                exists = !results.isEmpty
-            } catch {
-                exists = false
-            }
+        do {
+            let count = try context.count(for: fetchRequest)
+            return count > 0
+        } catch {
+            return false
         }
-        return exists
     }
 }

readeck/UI/Components/WebView.swift

@@ -285,6 +285,8 @@ class WebViewCoordinator: NSObject, WKNavigationDelegate, WKScriptMessageHandler
     var onHeightChange: ((CGFloat) -> Void)?
     var onScroll: ((Double) -> Void)?
     var hasHeightUpdate: Bool = false
+    var isScrolling: Bool = false
+    var scrollEndTimer: Timer?
     
     func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
         if navigationAction.navigationType == .linkActivated {
@@ -300,7 +302,8 @@ class WebViewCoordinator: NSObject, WKNavigationDelegate, WKScriptMessageHandler
     func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
         if message.name == "heightUpdate", let height = message.body as? CGFloat {
             DispatchQueue.main.async {
-                if self.hasHeightUpdate == false {
+                // Block height updates during active scrolling to prevent flicker
+                if !self.isScrolling && !self.hasHeightUpdate {
                     self.onHeightChange?(height)
                     self.hasHeightUpdate = true
                 }
@@ -308,6 +311,15 @@ class WebViewCoordinator: NSObject, WKNavigationDelegate, WKScriptMessageHandler
         }
         if message.name == "scrollProgress", let progress = message.body as? Double {
             DispatchQueue.main.async {
+                // Track scrolling state
+                self.isScrolling = true
+                
+                // Reset scrolling state after scroll ends
+                self.scrollEndTimer?.invalidate()
+                self.scrollEndTimer = Timer.scheduledTimer(withTimeInterval: 0.2, repeats: false) { _ in
+                    self.isScrolling = false
+                }
+                
                 self.onScroll?(progress)
             }
         }