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Co-authored-by: alex-vazquez-unity3d <129046031+alex-vazquez-unity3d@users.noreply.github.com>

Author: alex-vazquez-unity3d

com.unity.postprocessing/CHANGELOG.md

@@ -10,7 +10,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - **The entire `com.unity.postprocessing` package is now deprecated and no longer actively developed.**
   - For URP and HDRP projects, migrate to the integrated Volume-based post-processing system.
   - For Built-in Render Pipeline projects, consider migrating to URP.
-  - See [Post-processing Overview](https://docs.unity3d.com/Manual/PostProcessingOverview.html) for migration guidance.
+  - See [Post-processing Overview](https://docs.unity3d.com/Manual/urp/upgrading-from-birp.html) for migration guidance.
 - Added `[Obsolete]` attributes to `PostProcessVolume`, `PostProcessLayer`, and `PostProcessProfile` classes.
 - Added startup dialog notification that appears once per Unity session, with optional "Don't ask again on this computer" checkbox for permanent dismissal.
 

com.unity.postprocessing/PostProcessing/Editor/DeprecationNotice.cs

@@ -40,7 +40,7 @@ static void ShowDeprecationDialog()
                 "For URP and HDRP projects, use the integrated post-processing via the Volume framework.\n\n" +
                 "For Built-in Render Pipeline projects, consider migrating to URP.\n\n" +
                 "See documentation for migration guidance:\n" +
-                "https://docs.unity3d.com/Manual/PostProcessingOverview.html",
+                "https://docs.unity3d.com/Manual/urp/upgrading-from-birp.html",
                 "OK",
                 DialogOptOutDecisionType.ForThisUser,
                 k_DialogOptOutKey);