Merge branch '4.6' of https://github.com/craftcms/cms into 5.0

# Conflicts:
#	CHANGELOG.md
#	src/web/assets/cp/dist/cp.js
#	src/web/assets/cp/dist/cp.js.map

src/fields/Assets.php

@@ -747,7 +747,6 @@ protected function inputTemplateVariables(array|ElementQueryInterface $value = n
                 $variables['defaultSourcePath'] = array_map(function(VolumeFolder $folder) {
                     return $folder->getSourcePathInfo();
                 }, $folders);
-                $variables['preferStoredSource'] = true;
             }
         }
 

src/fields/BaseRelationField.php

@@ -610,7 +610,7 @@ public function isValueEmpty(mixed $value, ElementInterface $element): bool
      */
     public function normalizeValue(mixed $value, ?ElementInterface $element): mixed
     {
-        if ($value instanceof ElementQueryInterface) {
+        if ($value instanceof ElementQueryInterface || $value instanceof ElementCollection) {
             return $value;
         }
 
@@ -1301,7 +1301,12 @@ public function getInputSelectionCriteria(): array
     public function getSelectionCondition(): ?ElementConditionInterface
     {
         if ($this->_selectionCondition !== null && !$this->_selectionCondition instanceof ConditionInterface) {
-            $this->_selectionCondition = Craft::$app->getConditions()->createCondition($this->_selectionCondition);
+            $condition = Craft::$app->getConditions()->createCondition($this->_selectionCondition);
+            if (!empty($condition->getConditionRules())) {
+                $this->_selectionCondition = $condition;
+            } else {
+                $this->_selectionCondition = null;
+            }
         }
 
         return $this->_selectionCondition;

src/gql/base/ElementMutationResolver.php

@@ -18,6 +18,7 @@
 use GraphQL\Type\Definition\ResolveInfo;
 use GraphQL\Type\Definition\Type;
 use GraphQL\Type\Definition\WrappingType;
+use yii\web\ServerErrorHttpException;
 
 /**
  * Class MutationResolver
@@ -160,7 +161,22 @@ protected function saveElement(ElementInterface $element): ElementInterface
             $element->setScenario(Element::SCENARIO_LIVE);
         }
 
-        Craft::$app->getElements()->saveElement($element);
+        $isNotNew = $element->id;
+        if ($isNotNew) {
+            $lockKey = "element:$element->id";
+            $mutex = Craft::$app->getMutex();
+            if (!$mutex->acquire($lockKey, 15)) {
+                throw new ServerErrorHttpException('Could not acquire a lock to save the element.');
+            }
+        }
+
+        try {
+            Craft::$app->getElements()->saveElement($element);
+        } finally {
+            if ($isNotNew) {
+                $mutex->release($lockKey);
+            }
+        }
 
         if ($element->hasErrors()) {
             $validationErrors = [];

src/helpers/FileHelper.php

@@ -900,13 +900,11 @@ public static function getExtensionByMimeType($mimeType, $preferShort = false, $
      */
     public static function deleteFileAfterRequest(string $filename): void
     {
-        self::$_filesToBeDeleted[] = $filename;
-
-        if (count(self::$_filesToBeDeleted) === 1) {
-            Craft::$app->onAfterRequest(function() {
-                static::deleteQueuedFiles();
-            });
+        if (empty(self::$_filesToBeDeleted)) {
+            register_shutdown_function([static::class, 'deleteQueuedFiles']);
         }
+
+        self::$_filesToBeDeleted[] = $filename;
     }
 
     /**

src/web/assets/cp/src/js/BaseElementIndex.js

@@ -473,7 +473,12 @@ Craft.BaseElementIndex = Garnish.Base.extend(
 
       // Grab the localStorage step key up front, so we don's lose track of it when the default source's default
       // source path is selected
-      const stepKey = this.getSelectedSourceState('sourcePathStep');
+      let stepKey;
+      if (this.settings.context === 'index') {
+        stepKey = this.getSelectedSourceState('sourcePathStep');
+      } else {
+        stepKey = this.instanceState.sourcePathStep || null;
+      }
 
       this.selectDefaultSource();
 
@@ -1041,14 +1046,17 @@ Craft.BaseElementIndex = Garnish.Base.extend(
       }
 
       // Store the source path
-      this.setSelecetedSourceState(
-        'sourcePathStep',
+      const sourcePathStep =
         (this.sourcePaths[this.sourceKey]
           ? this.sourcePaths[this.sourceKey][
               this.sourcePaths[this.sourceKey].length - 1
             ].key
-          : null) || null
-      );
+          : null) || null;
+      if (this.settings.context === 'index') {
+        this.setSelecetedSourceState('sourcePathStep', sourcePathStep);
+      } else {
+        this.setInstanceState('sourcePathStep', sourcePathStep);
+      }
 
       this.onSourcePathChange();
     },

src/web/assets/cp/src/js/BaseElementSelectInput.js

@@ -9,6 +9,7 @@ Craft.BaseElementSelectInput = Garnish.Base.extend(
     elementSort: null,
     modal: null,
     elementEditor: null,
+    modalFirstOpen: true,
 
     $container: null,
     $form: null,
@@ -638,6 +639,7 @@ Craft.BaseElementSelectInput = Garnish.Base.extend(
 
       if (!this.modal) {
         this.modal = this.createModal();
+        this.modalFirstOpen = false;
       } else {
         this.modal.show();
       }
@@ -651,7 +653,7 @@ Craft.BaseElementSelectInput = Garnish.Base.extend(
     },
 
     getModalSettings: function () {
-      return $.extend(
+      const settings = $.extend(
         {
           closeOtherModals: false,
           storageKey: this.modalStorageKey,
@@ -671,6 +673,14 @@ Craft.BaseElementSelectInput = Garnish.Base.extend(
         },
         this.settings.modalSettings
       );
+
+      // make sure the previously-selected source is retained each time the
+      // modal is re-opened
+      if (!this.modalFirstOpen) {
+        settings.preferStoredSource = true;
+      }
+
+      return settings;
     },
 
     getSelectedElementIds: function () {