Quelle  popup_image_nomargin.xml

<?xml version="1.0" encoding="utf-8"?>
<com.google.android.material.card.MaterialCardView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    app:strokeWidth="0dp"
    app:cardCornerRadius="@dimen/cardview_border_radius"
    app:cardElevation="0dp">

    <androidx.appcompat.widget.AppCompatImageView
        android:id="@+id/thumbnail_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:adjustViewBounds="true"
        android:scaleType="fitXY" />

</com.google.android.material.card.MaterialCardView>