can't fine variable OfflineAudioContext in safari

I am using web audio API to stream audio to my remote server. I am using OfflineAudioContext. The code works fine in chrome and firefox but in safari, it gives the above mentioned error when trying to use OfflineAudioContext. I have tried adding webkit prefix to OfflineAudioContext, then it gives me this error:

SyntaxError: The string did not match the expected pattern.

I have tried adding different values to the OfflineAudioContext constructor but its always giving me the same error.

I went through Mozilla developers page for browser compatibility and I found this :

So, here its mentioned that for OfflineAudioContext constructor the compatibility is unknown for edge and safari. So, is this the reason, why I am not able to use OfflineAudioContext in safari? Is it not supported yet? or Am I doing it wrong? Or Is there another way to solve this in safari?

This is the first time I am using the Web Audio API. So, I hope somebody can clear my doubt if I missed out somewhere. Thank You.

Code of OfflineAudioContext added below:

let sourceAudioBuffer = e.inputBuffer; // directly received by the audioprocess event from the microphone in the browser

let TARGET_SAMPLE_RATE = 16000;
let OfflineAudioContext =
  window.OfflineAudioContext || window.webkitOfflineAudioContext;
let offlineCtx = new OfflineAudioContext(
  sourceAudioBuffer.numberOfChannels,
  sourceAudioBuffer.duration *
    sourceAudioBuffer.numberOfChannels *
    TARGET_SAMPLE_RATE,
  TARGET_SAMPLE_RATE
);

(if more code is needed of the js file to know the problem better. Just comment for it. I will add that but I thought the snippet is enough to understand the problem)