Is it really that easy?

entity-browser-image-support.patch

diff --git a/src/Plugin/Field/FieldWidget/EntityReference.php b/src/Plugin/Field/FieldWidget/EntityReference.php
index 004ab98..935c05f 100644
--- a/src/Plugin/Field/FieldWidget/EntityReference.php
+++ b/src/Plugin/Field/FieldWidget/EntityReference.php
@@ -33,7 +33,8 @@ use Symfony\Component\EventDispatcher\EventDispatcherInterface;
  *   description = @Translation("Uses entity browser to select entities."),
  *   multiple_values = TRUE,
  *   field_types = {
- *     "entity_reference"
+ *     "entity_reference",
+ *     "image"
  *   }
  * )
  */