blocked main thread because of PeerConnectionWrapper.removePeerConnection

seems to be a problem since v21.0.0

"main" tid=1 Native
  #00  pc 0x0000000000099000  /apex/com.android.runtime/lib64/bionic/libc.so (syscall+32)
  #01  pc 0x000000000009dc80  /apex/com.android.runtime/lib64/bionic/libc.so (__futex_wait_ex+148)
  #02  pc 0x0000000000104244  /apex/com.android.runtime/lib64/bionic/libc.so (pthread_cond_wait+80)
  #03  pc 0x00000000004729d8  /data/app/~~GQpUn6xfy4VS__fhG3FO0Q==/com.nextcloud.talk2-ea4fvHwzrTiOa66uf4oOTA==/base.apk (BuildId: 582f068037b18243)
  #04  pc 0x0000000000aaeefc  /data/app/~~GQpUn6xfy4VS__fhG3FO0Q==/com.nextcloud.talk2-ea4fvHwzrTiOa66uf4oOTA==/base.apk (BuildId: 582f068037b18243)
  #05  pc 0x0000000000aaef4c  /data/app/~~GQpUn6xfy4VS__fhG3FO0Q==/com.nextcloud.talk2-ea4fvHwzrTiOa66uf4oOTA==/base.apk (BuildId: 582f068037b18243)
  #06  pc 0x00000000003764f4  /data/app/~~GQpUn6xfy4VS__fhG3FO0Q==/com.nextcloud.talk2-ea4fvHwzrTiOa66uf4oOTA==/base.apk (BuildId: 582f068037b18243)
  at org.webrtc.JniCommon.nativeReleaseRef (Native method)
  at org.webrtc.DataChannel.dispose (DataChannel.java:173)
  at com.nextcloud.talk.webrtc.PeerConnectionWrapper.removePeerConnection (PeerConnectionWrapper.java:240)
  at com.nextcloud.talk.activities.CallActivity.endPeerConnection (CallActivity.kt:2508)
  at com.nextcloud.talk.activities.CallActivity.hangup (CallActivity.kt:2048)
  at com.nextcloud.talk.activities.CallActivity.initCallActionClickListeners$lambda$19 (CallActivity.kt:716)
  at com.nextcloud.talk.activities.CallActivity.$r8$lambda$sDK8z2GBQPzgvhGnB3OPzYOcpwA (unavailable)
  at com.nextcloud.talk.activities.CallActivity$$ExternalSyntheticLambda58.onClick (D8$$SyntheticClass)
  at android.view.View.performClick (View.java:7740)
  at android.view.View.performClickInternal (View.java:7710)
  at android.view.View.-$$Nest$mperformClickInternal (unavailable)
  at android.view.View$PerformClick.run (View.java:30629)
  at android.os.Handler.handleCallback (Handler.java:958)
  at android.os.Handler.dispatchMessage (Handler.java:99)
  at android.os.Looper.loopOnce (Looper.java:257)
  at android.os.Looper.loop (Looper.java:368)
  at android.app.ActivityThread.main (ActivityThread.java:8839)
  at java.lang.reflect.Method.invoke (Native method)
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:572)
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1049)

"signaling_threa - 13640" tid=74 Blocked
  at com.nextcloud.talk.webrtc.PeerConnectionWrapper$DataChannelObserver.onMessage (PeerConnectionWrapper.java:420)

Start by reading PeerConnectionWrapper.removePeerConnection at PeerConnectionWrapper.java:240 and DataChannelObserver.onMessage at PeerConnectionWrapper.java:420, then trace the hangup path through CallActivity.endPeerConnection and hangup. Reproduce the blocked-main-thread report during call termination; done means removing the peer connection no longer blocks the main thread.