RequestInit

abstract val body: UndefOr[BodyInit]

abstract val credentials: UndefOr[RequestCredentials]

abstract val headers: UndefOr[HeadersInit]

abstract val integrity: UndefOr[String]

abstract val method: UndefOr[HttpMethod]

abstract val mode: UndefOr[RequestMode]

abstract val referrer: UndefOr[String]

abstract val referrerPolicy: UndefOr[ReferrerPolicy]

abstract val requestCache: UndefOr[RequestCache]

abstract val requestRedirect: UndefOr[RequestRedirect]

abstract val window: UndefOr[Null]

The whatwg spec section on RequestInit dictionary has a comment that states that this value "can only be set to null".

final def !=(arg0: AnyRef): Boolean

final def !=(arg0: Any): Boolean

final def ##(): Int

final def ==(arg0: AnyRef): Boolean

final def ==(arg0: Any): Boolean

final def asInstanceOf[T0]: T0

def clone(): AnyRef

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

final def getClass(): Class[_]

def hasOwnProperty(v: String): Boolean

def hashCode(): Int

final def isInstanceOf[T0]: Boolean

def isPrototypeOf(v: Object): Boolean

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

def propertyIsEnumerable(v: String): Boolean

final def synchronized[T0](arg0: ⇒ T0): T0

def toLocaleString(): String

def toString(): String

def valueOf(): Any

final def wait(): Unit

final def wait(arg0: Long, arg1: Int): Unit

final def wait(arg0: Long): Unit