Cannot capture websocket traffic from Android

[Alexander]

I have installed Fiddler certificate to my Android device. I see decrypted https traffic, but there are no websocket requests.What can be the reason of this problem?

[Simeon]

Hello Alexander,

What is the application you are trying to debug? Is it possible for you to provide me with some steps to reproduce the problem. What is the Android device and the Android version which you are using?

Regards,
Simeon
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[Alexander]

Hi Simeon,

It's application based on rocketchat. This chat uses websocket for connecting and sending messages. I tried different devices, for example Nexus 5, Android 6.0.1; Samsung Galaxy S5, Android 6.0.1; Nexus 5X, Android 8.0. Actually, I have the same problem with iOS (iPhone 7, iOS 11; iPhone X, iOS 11; iPhone 5, iOS 10.3.3). 

It seems to me, that I didn't set up some settings in Fiddler.

[Simeon]

I am not familiar with Rocketchat, but after some research I landed on this issue: https://github.com/RocketChat/Rocket.Chat.Electron/issues/421, which states that it does not work behind a proxy, which Fiddler is.

Could you, please, try the solutions provided into the issue and its related issues.

Another option is to set Fiddler as a reverse proxy for the Rocketchat server.

Please, let me know if something of the mentioned above helps.

Thanks and Regards,
Simeon
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