diff --git a/color_field.module b/color_field.module
--- a/color_field.module	(revision d5ad2f542b5920542efb83a41cae8931134ca316)
+++ b/color_field.module	(revision a3929b4424ae92a3b47e31bbb1b218d04ec02fd1)
@@ -208,7 +208,7 @@
  *
  * Include the color_field in exports by the single_content_sync module.
  */
-function color_field_content_export_field_value_alter(mixed &$value, FieldItemListInterface $field): void {
+function color_field_content_export_field_value_alter(&$value, FieldItemListInterface $field): void {
   switch ($field->getFieldDefinition()->getType()) {
     case 'color_field_type':
       $value[] = [
Index: src/ColorHex.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/ColorHex.php b/src/ColorHex.php
--- a/src/ColorHex.php	(revision d5ad2f542b5920542efb83a41cae8931134ca316)
+++ b/src/ColorHex.php	(revision a3929b4424ae92a3b47e31bbb1b218d04ec02fd1)
@@ -30,7 +30,7 @@
   public function __construct(string $color, ?string $opacity) {
     $color = trim(strtolower($color));

-    if (str_starts_with($color, '#')) {
+    if (strpos($color, '#') === 0) {
       $color = substr($color, 1);
     }

Index: src/Feeds/Target/Color.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/Feeds/Target/Color.php b/src/Feeds/Target/Color.php
--- a/src/Feeds/Target/Color.php	(revision d5ad2f542b5920542efb83a41cae8931134ca316)
+++ b/src/Feeds/Target/Color.php	(revision a3929b4424ae92a3b47e31bbb1b218d04ec02fd1)
@@ -69,7 +69,7 @@
     // Clean up data and format it.
     $color = trim($values['color']);

-    if (str_starts_with($color, '#')) {
+    if (strpos($color, '#') === 0) {
       $color = substr($color, 1);
     }

Index: src/Plugin/Field/FieldFormatter/ColorFieldFormatterCss.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/Plugin/Field/FieldFormatter/ColorFieldFormatterCss.php b/src/Plugin/Field/FieldFormatter/ColorFieldFormatterCss.php
--- a/src/Plugin/Field/FieldFormatter/ColorFieldFormatterCss.php	(revision d5ad2f542b5920542efb83a41cae8931134ca316)
+++ b/src/Plugin/Field/FieldFormatter/ColorFieldFormatterCss.php	(revision a3929b4424ae92a3b47e31bbb1b218d04ec02fd1)
@@ -47,7 +47,7 @@
    *
    * @param string $plugin_id
    *   The plugin_id for the formatter.
-   * @param mixed $plugin_definition
+   * @param $plugin_definition
    *   The plugin implementation definition.
    * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
    *   The definition of the field to which the formatter is associated.
@@ -64,7 +64,7 @@
    * @param \Drupal\token\TokenEntityMapperInterface|null $token_entity_mapper
    *   Optional token entity mapper service.
    */
-  public function __construct(string $plugin_id, mixed $plugin_definition, FieldDefinitionInterface $field_definition, array $settings, string $label, string $view_mode, array $third_party_settings, Token $token_service, ?TokenEntityMapperInterface $token_entity_mapper = NULL) {
+  public function __construct(string $plugin_id, $plugin_definition, FieldDefinitionInterface $field_definition, array $settings, string $label, string $view_mode, array $third_party_settings, Token $token_service, ?TokenEntityMapperInterface $token_entity_mapper = NULL) {
     parent::__construct($plugin_id, $plugin_definition, $field_definition, $settings, $label, $view_mode, $third_party_settings);
     $this->tokenService = $token_service;
     $this->tokenEntityMapper = $token_entity_mapper;
Index: src/Plugin/Field/FieldFormatter/ColorFieldFormatterSwatch.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/Plugin/Field/FieldFormatter/ColorFieldFormatterSwatch.php b/src/Plugin/Field/FieldFormatter/ColorFieldFormatterSwatch.php
--- a/src/Plugin/Field/FieldFormatter/ColorFieldFormatterSwatch.php	(revision d5ad2f542b5920542efb83a41cae8931134ca316)
+++ b/src/Plugin/Field/FieldFormatter/ColorFieldFormatterSwatch.php	(revision a3929b4424ae92a3b47e31bbb1b218d04ec02fd1)
@@ -161,7 +161,7 @@
    * @return \Drupal\Component\Render\MarkupInterface[]|\Drupal\Component\Render\MarkupInterface
    *   An array of shape ids/names or translated name of the specified shape.
    */
-  protected function getShape(?string $shape = NULL): array|MarkupInterface {
+  protected function getShape(?string $shape = NULL): array {
     $formats = [];
     $formats['square'] = $this->t('Square');
     $formats['circle'] = $this->t('Circle');
Index: src/Plugin/Field/FieldFormatter/ColorFieldFormatterText.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/Plugin/Field/FieldFormatter/ColorFieldFormatterText.php b/src/Plugin/Field/FieldFormatter/ColorFieldFormatterText.php
--- a/src/Plugin/Field/FieldFormatter/ColorFieldFormatterText.php	(revision d5ad2f542b5920542efb83a41cae8931134ca316)
+++ b/src/Plugin/Field/FieldFormatter/ColorFieldFormatterText.php	(revision a3929b4424ae92a3b47e31bbb1b218d04ec02fd1)
@@ -103,7 +103,7 @@
    * @return \Drupal\Component\Render\MarkupInterface[]|\Drupal\Component\Render\MarkupInterface
    *   Returns array or string.
    */
-  protected function getColorFormat(?string $format = NULL): array|MarkupInterface {
+  protected function getColorFormat(?string $format = NULL): array {
     $formats = [];
     $formats['hex'] = $this->t('Hex triplet');
     $formats['rgb'] = $this->t('RGB Decimal');
Index: src/Plugin/Field/FieldType/ColorFieldType.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/Plugin/Field/FieldType/ColorFieldType.php b/src/Plugin/Field/FieldType/ColorFieldType.php
--- a/src/Plugin/Field/FieldType/ColorFieldType.php	(revision d5ad2f542b5920542efb83a41cae8931134ca316)
+++ b/src/Plugin/Field/FieldType/ColorFieldType.php	(revision a3929b4424ae92a3b47e31bbb1b218d04ec02fd1)
@@ -138,7 +138,7 @@
       // Clean up data and format it.
       $color = trim($color);

-      if (str_starts_with($color, '#')) {
+      if (strpos($color, '#') === 0) {
         $color = substr($color, 1);
       }
       switch ($format) {
Index: src/Plugin/Field/FieldWidget/ColorFieldWidgetBase.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/Plugin/Field/FieldWidget/ColorFieldWidgetBase.php b/src/Plugin/Field/FieldWidget/ColorFieldWidgetBase.php
--- a/src/Plugin/Field/FieldWidget/ColorFieldWidgetBase.php	(revision d5ad2f542b5920542efb83a41cae8931134ca316)
+++ b/src/Plugin/Field/FieldWidget/ColorFieldWidgetBase.php	(revision a3929b4424ae92a3b47e31bbb1b218d04ec02fd1)
@@ -26,7 +26,7 @@
     if (isset($items[$delta]->color)) {
       $color = $items[$delta]->color;

-      if (!str_starts_with($color, '#')) {
+      if (!(strpos($color, '#') === 0)) {
         $color = '#' . $color;
       }
     }