fix: use file name in resizable panel if available

packages/core/src/components/entry-editor/EditorInterface.tsx

@@ -242,6 +242,8 @@ const EditorInterface: FC<EditorInterfaceProps> = ({
     setSelectedLocale(locale);
   }, []);
 
+  const file = getFileFromSlug(collection, entry.slug);
+
   const { livePreviewUrlTemplate, showPreviewToggle, previewInFrame, editorSize } = useMemo(() => {
     let livePreviewUrlTemplate =
       typeof collection.editor?.live_preview === 'string' ? collection.editor.live_preview : false;
@@ -261,8 +263,6 @@ const EditorInterface: FC<EditorInterfaceProps> = ({
     }
 
     if ('files' in collection) {
-      const file = getFileFromSlug(collection, entry.slug);
-
       if (file?.editor) {
         if (typeof file.editor.live_preview === 'string') {
           livePreviewUrlTemplate = file.editor.live_preview;
@@ -417,8 +417,8 @@ const EditorInterface: FC<EditorInterfaceProps> = ({
     <>
       {!isSmallScreen ? (
         <PanelGroup
-          key={`editor-with-preview-${editorSize}`}
-          autoSaveId={`editor-with-preview-${collection.name}`}
+          key="editor-with-preview"
+          autoSaveId={`editor-with-preview-${collection.name}${file ? `-${file.name}` : ''}`}
           direction="horizontal"
           units={editorSize === EDITOR_SIZE_COMPACT ? 'pixels' : 'percentages'}
           className={classNames(

packages/core/src/lib/util/collection.util.ts

@@ -14,21 +14,22 @@ import { keyToPathArray } from '../widgets/stringTemplate';
 import { selectField } from './field.util';
 import { selectMediaFolder } from './media.util';
 
-import type { InferrableField } from '@staticcms/core/constants/fieldInference';
 import type {
   BaseField,
-  CollectionWithDefaults,
+  Collection,
+  CollectionFile,
   CollectionFileWithDefaults,
+  CollectionWithDefaults,
   CollectionsWithDefaults,
   Config,
   ConfigWithDefaults,
   Entry,
   Field,
-  FilesCollection,
   InferredField,
   ObjectField,
   SortableField,
 } from '@staticcms/core';
+import type { InferrableField } from '@staticcms/core/constants/fieldInference';
 
 export function fileForEntry<EF extends BaseField>(
   collection: CollectionWithDefaults<EF> | undefined | null,
@@ -282,9 +283,13 @@ function getFieldsWithMediaFolders<EF extends BaseField>(fields: Field<EF>[]) {
 }
 
 export function getFileFromSlug<EF extends BaseField>(
-  collection: FilesCollection<EF>,
+  collection: Collection<EF>,
   slug: string,
-) {
+): CollectionFile<EF> | undefined {
+  if (!('files' in collection)) {
+    return undefined;
+  }
+
   return collection.files?.find(f => f.name === slug);
 }