Sponsorblock does not work in the background (i.e. audio-only) play

[in-plaintext]

Checklist

• I am able to reproduce the bug with the latest version.
• I am not able to reproduce the bug with the latest version of vanilla NewPipe.
• I made sure that there are no existing issues - open or closed - which I could contribute my information to.
• I have read the FAQ and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
• This issue contains only one bug.
• I have read and understood the vanilla NewPipe contribution guidelines.

Affected version

v0.27.2

Steps to reproduce the bug

1. open any Youtube video containing Sponsorblock segments
2. inspect how none of the segments are ever skipped in the background player

Expected behavior

Sponsorblock should work equally in both the video and audio (the background) player.

Actual behavior

None of the Sponsorblock's segments are ever skipped in the background player

Screenshots/Recordings

No response

Logs

No response

Affected Android/Custom ROM version

No response

Affected device model

No response

Additional information

the same issue for the preceding fork: polymorphicshade/NewPipe#257
a related issue about downloads: #117