Playback stalls after seek

[HokkanenTeemu]

Have you read the FAQ and checked for duplicate open issues?
Yes

If the problem is related to FairPlay, have you read the tutorial?

N/A

What version of Shaka Player are you using?

I'm using 4.11.4 in production at the moment but I have tested multiple versions, including the latest 4.13.0.
From what I have gathered, latest version without the issue seems to be 4.9.35.

Can you reproduce the issue with our latest release version?
Yes

Can you reproduce the issue with the latest code from main?
Yes

Are you using the demo app or your own custom app?
Custom app

If custom app, can you reproduce the issue using our demo app?
Yes

What browser and OS are you using?
Safari on iOS/iPadOS/macOS
I have been able to reproduce the issue on all versions (where MSE/MMS is available) that I have tested except the latest 18.2

For embedded devices (smart TVs, etc.), what model and firmware version are you using?
N/A

What are the manifest and license server URIs?

The issue was discovered with our own streams but this stream from hls.js demo page works also:
https://test-streams.mux.dev/x36xhzz/x36xhzz.m3u8
I tried to reproduce the issue with streams from shaka-player demo page but those seemed to work without an issue.

What configuration are you using? What is the output of player.getNonDefaultConfiguration()?

Default configuration

What did you do?

I tried to seek HLS stream while using shaka-player on iOS device in Safari browser. Simplified example:

<video muted autoplay playsinline controls></video>

<script>
  (async () => {
    const video = document.querySelector('video')

    const url = 'https://test-streams.mux.dev/x36xhzz/x36xhzz.m3u8' 

    // for testing, can be reproduced without
    shaka.polyfill.installAll()
    shaka.log.setLevel(shaka.log.Level.V2)

    const player = new shaka.Player()
    await player.attach(video)
    await player.load(url)
    
    // just one of the ways to reproduce the issue consistently
    await new Promise(r => setTimeout(r, 15000))
    video.currentTime = 3
  })()
</script>

What did you expect to happen?
The playback not to stall

What actually happened?

Playback sometimes stalls after seeking. Smaller seeks seem to work better but larger seeks cause the playback to stall very often.
From the logs I can only see that shaka detects the stall but is not able to recover from it.

Are you planning to send a PR to fix it?
Not at the moment