diff --git a/AgoraUIKit_iOS.podspec b/AgoraUIKit_iOS.podspec
index 12b723d8..fd38688a 100644
--- a/AgoraUIKit_iOS.podspec
+++ b/AgoraUIKit_iOS.podspec
@@ -8,7 +8,7 @@
 
 Pod::Spec.new do |s|
   s.name             = 'AgoraUIKit_iOS'
-  s.version          = '4.0.0-preview.5'
+  s.version          = '4.0.0-preview.6'
   s.summary          = 'Agora video session UIKit template.'
 
   s.description      = <<-DESC
diff --git a/Sources/Agora-UIKit/AgoraUIKit.swift b/Sources/Agora-UIKit/AgoraUIKit.swift
index 756d5a68..20873bb7 100644
--- a/Sources/Agora-UIKit/AgoraUIKit.swift
+++ b/Sources/Agora-UIKit/AgoraUIKit.swift
@@ -22,7 +22,7 @@ public struct AgoraUIKit: Codable {
     /// Framework type of UIKit. "native", "flutter", "reactnative"
     fileprivate(set) var framework: String
     /// Version of UIKit being used
-    static let version = "4.0.0-preview.5"
+    static let version = "4.0.0-preview.6"
     /// Framework type of UIKit. "native", "flutter", "reactnative"
     static let framework = "native"
     #if os(iOS)
diff --git a/Sources/Agora-UIKit/AgoraVideoViewer+AgoraExtensions.swift b/Sources/Agora-UIKit/AgoraVideoViewer+AgoraExtensions.swift
index ce2d86b4..e44b0ef7 100644
--- a/Sources/Agora-UIKit/AgoraVideoViewer+AgoraExtensions.swift
+++ b/Sources/Agora-UIKit/AgoraVideoViewer+AgoraExtensions.swift
@@ -15,7 +15,7 @@ extension AgoraVideoViewer {
     ///   - enabled: enable or disable. - true: enable. - false: disable.
     /// - Returns: `0`: Success. `<0`: Failure.
     @discardableResult
-    func enableExtension(withVendor vendor: String, extension extString: String, enabled: Bool) -> Int32 {
+    open func enableExtension(withVendor vendor: String, extension extString: String, enabled: Bool) -> Int32 {
         return self.agkit.enableExtension(withVendor: vendor, extension: extString, enabled: enabled)
     }
 
@@ -27,7 +27,7 @@ extension AgoraVideoViewer {
     ///   - value: string value to set.
     /// - Returns: `0` = Success. `<0` = Failure.
     @discardableResult
-    func setExtensionProperty(
+    open func setExtensionProperty(
         _ vendor: String, extension extString: String, key: String, value: String
     ) -> Int32 {
         return self.agkit.setExtensionPropertyWithVendor(
@@ -44,7 +44,7 @@ extension AgoraVideoViewer {
     ///   - codable: value to set for the property, must be encodable to a JSON string.
     /// - Returns: `0` = Success. `<0` = Failure.
     @discardableResult
-    func setExtensionProperty<T>(
+    open func setExtensionProperty<T>(
         _ vendor: String, extension extString: String, key: String, codable: T
     ) -> Int32? where T: Encodable {
         guard let encodedData = try? JSONEncoder().encode(codable),
@@ -66,7 +66,7 @@ extension AgoraVideoViewer {
     ///   - strValue: string value to set.
     /// - Returns: `0` = Success. `<0` = Failure.
     @discardableResult
-    func setExtensionProperty(
+    open func setExtensionProperty(
         _ vendor: String, extension extString: String, key: String, strValue: String
     ) -> Int32 {
         return self.agkit.setExtensionPropertyWithVendor(
@@ -83,7 +83,7 @@ extension AgoraVideoViewer {
     ///   - value: Boolean value to set.
     /// - Returns: `0` = Success. `<0` = Failure.
     @discardableResult
-    func setExtensionProperty(
+    open func setExtensionProperty(
         _ vendor: String, extension extString: String, key: String, value: Bool
     ) -> Int32 {
         return self.agkit.setExtensionPropertyWithVendor(