It appears that something happened to the published artifacts of firebase-crashlytics-ktx in version 18.5.0 and later.
Version 18.4.3 seems to be the last version that wasn't broken.
Specifically this is missing from the newer artifacts (in package com.google.firebase.crashlytics.ktx ):
/** Returns the [FirebaseCrashlytics] instance of the default [FirebaseApp]. */
val Firebase.crashlytics: FirebaseCrashlytics
get() = FirebaseCrashlytics.getInstance()
/** Associates all key-value parameters with the reports */
fun FirebaseCrashlytics.setCustomKeys(init: KeyValueBuilder.() -> Unit) {
val builder = KeyValueBuilder(this)
builder.init()
} 
It appears that something happened to the published artifacts of
firebase-crashlytics-ktxin version18.5.0and later.Version
18.4.3seems to be the last version that wasn't broken.Specifically this is missing from the newer artifacts (in
package com.google.firebase.crashlytics.ktx):