Index: ../../git/magnolia-5.4-repo/ui/magnolia-ui-dialog/src/main/java/info/magnolia/ui/dialog/formdialog/FormPresenterImpl.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- ../../git/magnolia-5.4-repo/ui/magnolia-ui-dialog/src/main/java/info/magnolia/ui/dialog/formdialog/FormPresenterImpl.java	(revision 7203fef314cb301f7e023083337f688ba63b90af)
+++ ../../git/magnolia-5.4-repo/ui/magnolia-ui-dialog/src/main/java/info/magnolia/ui/dialog/formdialog/FormPresenterImpl.java	(revision )
@@ -35,6 +35,7 @@
 
 import info.magnolia.ui.api.app.SubAppContext;
 import info.magnolia.ui.api.context.UiContext;
+import info.magnolia.ui.api.i18n.I18NAuthoringSupport;
 import info.magnolia.ui.form.FormItem;
 import info.magnolia.ui.form.FormPresenter;
 import info.magnolia.ui.form.definition.FormDefinition;
@@ -86,10 +87,13 @@
 
     private Item itemDatasource;
 
+    private final I18NAuthoringSupport i18nAuthoringSupport;
+
     @Inject
-    public FormPresenterImpl(FormBuilder formBuilder, UiContext uiContext) {
+    public FormPresenterImpl(FormBuilder formBuilder, UiContext uiContext, I18NAuthoringSupport i18nAuthoringSupport) {
         this.formBuilder = formBuilder;
         this.uiContext = uiContext;
+        this.i18nAuthoringSupport = i18nAuthoringSupport;
     }
 
     @Override
@@ -104,11 +108,17 @@
 
         // We should expand locale-awareness onto all the UI contexts.
         if (uiContext instanceof SubAppContext) {
-            this.activeLocale = ((SubAppContext)uiContext).getAuthoringLocale();
+            this.activeLocale = ((SubAppContext) uiContext).getAuthoringLocale();
+
+            // In case active Local does not exist, get default locale instead
+            if (this.activeLocale == null) {
+                this.activeLocale = i18nAuthoringSupport.getDefaultLocale(item);
+            }
+
             formView.setListener(new FormView.Listener() {
                 @Override
                 public void localeChanged(Locale newLocale) {
-                    if (newLocale != null && !ObjectUtils.equals(((SubAppContext)uiContext).getAuthoringLocale(), newLocale)) {
+                    if (newLocale != null && !ObjectUtils.equals(((SubAppContext) uiContext).getAuthoringLocale(), newLocale)) {
                         setLocale(newLocale);
                     }
                 }
@@ -134,7 +144,7 @@
         if (uiContext instanceof SubAppContext && !ObjectUtils.equals(locale, this.activeLocale)) {
             final Locale formerLocale = this.activeLocale;
             this.activeLocale = locale;
-            ((SubAppContext)uiContext).setAuthoringLocale(locale);
+            ((SubAppContext) uiContext).setAuthoringLocale(locale);
 
             final Map<TabDefinition, FormSection> currentFormSections = localeToFormSections.get(formerLocale);
             final Map<TabDefinition, FormSection> newFormSections = getLocaleSpecificFormSections(this.activeLocale);
Index: ../../git/magnolia-5.4-repo/ui/magnolia-ui-dialog/src/test/java/info/magnolia/ui/dialog/formdialog/FormPresenterImplTest.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- ../../git/magnolia-5.4-repo/ui/magnolia-ui-dialog/src/test/java/info/magnolia/ui/dialog/formdialog/FormPresenterImplTest.java	(revision 7203fef314cb301f7e023083337f688ba63b90af)
+++ ../../git/magnolia-5.4-repo/ui/magnolia-ui-dialog/src/test/java/info/magnolia/ui/dialog/formdialog/FormPresenterImplTest.java	(revision )
@@ -114,7 +114,7 @@
         doReturn(mock(BasicTransformer.class)).when(componentProvider).newInstance(eq(BasicTransformer.class), anyVararg());
         this.item = new PropertysetItem();
         this.formBuilder = new FormBuilder(fieldFactoryFactory, i18NAuthoringSupport, subAppContext, componentProvider);
-        this.formPresenter = new FormPresenterImpl(formBuilder, subAppContext);
+        this.formPresenter = new FormPresenterImpl(formBuilder, subAppContext, i18NAuthoringSupport);
         this.formView = new ItemFormView(i18n);
     }
 
\ No newline at end of file