getSeekableBlob broken on Chrome ≥136 (Windows) when using RecordRTC v5.6.2

After the Chrome 136 update (Windows), getSeekableBlob no longer works.

It throws the following errors

1. Using video/webm;codecs=vp8 / vp9 / video/webm → runtime error: No schema entry found for unknown

2. Using video/mp4 → runtime error: Unpresentable length: <some number>

Sample Code to Reproduce the Issue

let recorder: RecordRTC;
stream;

function startRecording() {
  stream = await navigator.mediaDevices.getUserMedia({
    video: true,
    audio: true,
  });

  recorder = new RecordRTC(stream, {
    type: 'video',
    mimeType: 'video/webm;codecs=vp8',
    // other settings
  });

  recorder.startRecording();
}

stopRecording() {

  recorder.stopRecording(() => {
    const blob = recorder.getBlob();

      getSeekableBlob(blob, (seekableBlob) => {
        // Rest processing
      });
}

1. Run this code on Chrome 136 or above (Windows).
2. Observe that getSeekableBlob fails with: No schema entry found for unknown

Expected Behavior:

getSeekableBlob should process the recorded blob and return a seekable WebM blob.

Actual Behavior:

On Chrome 136+, the function throws runtime errors

The same code works fine on Chrome <136.

Environment:

RecordRTC: 5.6.2

Browser: Chrome 136 (also tested on 139, 138, 137)

OS: Windows 10/11, Works fine on linux or mac