material-components-android/lib/java/com/google/android/material/internal/ VisibilityAwareImageButton.java at master · material-components/material-components-android · GitHub
FAB set visibility: VisibilityAwareImageButton.setVisibility can only be called from within the same library group (groupId=com.android.support) · Issue #9 · yongyanghz/Summary-Of-Android-Development-Issues-I-met · GitHub
Calendar View show/gone inside Recyclerview ViewHolder Issue on Android 8, 9 only - Stack Overflow