diff --git a/plugins/adapter.inc b/plugins/adapter.inc
index 3411c45..64f72b7 100644
--- a/plugins/adapter.inc
+++ b/plugins/adapter.inc
@@ -1172,13 +1172,15 @@ class FacetapiFacet implements ArrayAccess {
   /**
    * Implements ArrayAccess::offsetExists().
    */
-  public function offsetExists($offset) {
+  #[\ReturnTypeWillChange]
+   public function offsetExists($offset) {
     return isset($this->facet[$offset]);
   }
 
   /**
    * Implements ArrayAccess::offsetGet().
    */
+  #[\ReturnTypeWillChange]
   public function offsetGet($offset) {
     return isset($this->facet[$offset]) ? $this->facet[$offset] : NULL;
   }
@@ -1186,6 +1188,7 @@ class FacetapiFacet implements ArrayAccess {
   /**
    * Implements ArrayAccess::offsetSet().
    */
+  #[\ReturnTypeWillChange]
   public function offsetSet($offset, $value) {
     if (NULL === $offset) {
       $this->facet[] = $value;
@@ -1198,6 +1201,7 @@ class FacetapiFacet implements ArrayAccess {
   /**
    * Implements ArrayAccess::offsetUnset().
    */
+  #[\ReturnTypeWillChange]
   public function offsetUnset($offset) {
     unset($this->facet[$offset]);
   }