#  WebRTC duplicated Class RTCVideoFrameBuffer with iOS system library of iOS13

**URL:** <https://react-native-webrtc.discourse.group/t/webrtc-duplicated-class-rtcvideoframebuffer-with-ios-system-library-of-ios13/378>\
**Category:** iOS\
**Created:** [November 22, 2019, 4:02pm UTC](https://react-native-webrtc.discourse.group/t/webrtc-duplicated-class-rtcvideoframebuffer-with-ios-system-library-of-ios13/378 "2019-11-22T16:02:39Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![thanphamngoc](https://avatars.discourse-cdn.com/v4/letter/t/87869e/32.png) [@thanphamngoc](https://react-native-webrtc.discourse.group/u/thanphamngoc)\
**Post date:** [November 22, 2019, 4:02pm UTC](https://react-native-webrtc.discourse.group/t/webrtc-duplicated-class-rtcvideoframebuffer-with-ios-system-library-of-ios13/378/1 "2019-11-22T16:02:39Z")

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Xcode: 11.2.1  
IOS: 13.2.2  
React-native: 0.61.1  
React-native-webrtc: 1.75.0

> objc[339]: Class RTCCVPixelBuffer is implemented in both /System/Library/PrivateFrameworks/WebCore.framework/Frameworks/libwebrtc.dylib (0x1d1862f98) and /private/var/containers/Bundle/Application/A0EA73B4-57EF-409B-B151-7FF7A3EEEB0C/TestApp.app/Frameworks/WebRTC.framework/WebRTC (0x10176fdc0).

One of the two will be used. Which one is undefined.

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**Author:** ![saghul](https://yyz2.discourse-cdn.com/free1/user_avatar/react-native-webrtc.discourse.group/saghul/32/4_2.png) [@saghul](https://react-native-webrtc.discourse.group/u/saghul)\
**Post date:** [November 22, 2019, 4:03pm UTC](https://react-native-webrtc.discourse.group/t/webrtc-duplicated-class-rtcvideoframebuffer-with-ios-system-library-of-ios13/378/2 "2019-11-22T16:03:33Z")

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THis is a known and harmless warning, you can ignore it. It’s because Apple doesn’t properlyhide those symbols, nothing we can do about it.