change: favorite merge rule

fix: page progress renderer

Pixiview/Illust/ViewIllustPage.xaml.cs

@@ -122,7 +122,8 @@ namespace Pixiview.Illust
         private IllustUgoiraData ugoiraData;
         private Ugoira ugoira;
 
-        private volatile int downloaded = 0;
+        private readonly object sync = new object();
+        private int downloaded = 0;
         private int pageCount;
 
         public ViewIllustPage(IllustItem illust, bool save)
@@ -413,11 +414,15 @@ namespace Pixiview.Illust
                 return;
             }
 
-            downloaded++;
+            lock (sync)
+            {
+                downloaded++;
+            }
             if (downloaded >= pageCount)
             {
                 MainThread.BeginInvokeOnMainThread(async () =>
                 {
+                    ViewExtensions.CancelAnimations(progress);
                     await progress.ProgressTo(1, 250, Easing.CubicIn);
                     await progress.FadeTo(0, easing: Easing.CubicIn);
                     ProgressVisible = false;