Suspend functions that use CoroutineScope as receiver should not be marked as suspend. A CoroutineScope provides structured concurrency via its coroutineContext. A suspend function also has its own coroutineContext, which is now ambiguous and mixed with the receiver`s.

Noncompliant Code

suspend fun CoroutineScope.foo() {
  launch {
    delay(1.seconds)
  }
}

Compliant Code

fun CoroutineScope.foo() {
    launch {
      delay(1.seconds)
    }
}

// Alternative
suspend fun foo() = coroutineScope {
    launch {
      delay(1.seconds)
    }
}