// WITH_RUNTIME
// INTENTION_TEXT: "Replace with 'flatMap{}.firstOrNull{}'"
// INTENTION_TEXT_2: "Replace with 'asSequence().flatMap{}.firstOrNull{}'"
fun foo(list: List<String>): String? {
    val <caret>result: String? = list
        .asSequence()
        .flatMap { it.lines().asSequence() }
        .firstOrNull { it.isNotBlank() }
    return result
}