diff --git a/com.woltlab.wcf/templates/shared_radioButtonFormField.tpl b/com.woltlab.wcf/templates/shared_radioButtonFormField.tpl
index 1d2add11ff7..e93a26c95c4 100644
--- a/com.woltlab.wcf/templates/shared_radioButtonFormField.tpl
+++ b/com.woltlab.wcf/templates/shared_radioButtonFormField.tpl
@@ -1,3 +1,16 @@
+{if !$field->isRequired()}
+	<label>
+		<input {*
+			*}type="radio" {*
+			*}name="{$field->getPrefixedId()}" {*
+			*}value="" {*
+			*}{if !$field->getFieldClasses()|empty} class="{implode from=$field->getFieldClasses() item='class' glue=' '}{$class}{/implode}"{/if}{*
+			*}{if $field->getValue() === null || $field->getValue() === ''} checked{/if}{*
+			*}{if $field->isImmutable()} disabled{/if}{*
+			*}{foreach from=$field->getFieldAttributes() key='attributeName' item='attributeValue'} {$attributeName}="{$attributeValue}"{/foreach}{*
+		*}> {lang}wcf.global.noSelection{/lang}
+	</label>
+{/if}
 {foreach from=$field->getOptions() key=$__fieldValue item=__fieldLabel}
 	<label>
 		<input {*
diff --git a/wcfsetup/install/files/lib/acp/form/DevtoolsProjectAddForm.class.php b/wcfsetup/install/files/lib/acp/form/DevtoolsProjectAddForm.class.php
index 25ce291d5a1..c7363e5f0d8 100644
--- a/wcfsetup/install/files/lib/acp/form/DevtoolsProjectAddForm.class.php
+++ b/wcfsetup/install/files/lib/acp/form/DevtoolsProjectAddForm.class.php
@@ -101,6 +101,7 @@ protected function createForm()
 
         $mode = RadioButtonFormField::create('mode')
             ->label('wcf.acp.devtools.project.add.mode')
+            ->required()
             ->options(function () {
                 $options = [
                     'import' => 'wcf.acp.devtools.project.add.mode.import',
diff --git a/wcfsetup/install/files/lib/acp/form/LanguageItemAddForm.class.php b/wcfsetup/install/files/lib/acp/form/LanguageItemAddForm.class.php
index 7c5f6589b28..e3d379490ae 100644
--- a/wcfsetup/install/files/lib/acp/form/LanguageItemAddForm.class.php
+++ b/wcfsetup/install/files/lib/acp/form/LanguageItemAddForm.class.php
@@ -68,6 +68,7 @@ protected function createForm()
             ->label('wcf.global.form.data')
             ->appendChildren([
                 RadioButtonFormField::create('languageCategoryIDMode')
+                    ->required()
                     ->label('wcf.acp.language.item.languageCategoryID.mode')
                     ->options([
                         'automatic' => 'wcf.acp.language.item.languageCategoryID.mode.automatic',
diff --git a/wcfsetup/install/files/lib/acp/form/MenuItemAddForm.class.php b/wcfsetup/install/files/lib/acp/form/MenuItemAddForm.class.php
index a439adc432e..9c0de3151dd 100644
--- a/wcfsetup/install/files/lib/acp/form/MenuItemAddForm.class.php
+++ b/wcfsetup/install/files/lib/acp/form/MenuItemAddForm.class.php
@@ -146,7 +146,8 @@ protected function createForm()
                             0 => 'wcf.acp.menu.item.link.external',
                             1 => 'wcf.acp.menu.item.link.internal',
                         ])
-                        ->value(1),
+                        ->value(1)
+                        ->required(),
                     SingleSelectionFormField::create('pageID')
                         ->label('wcf.acp.page.page')
                         ->options($pageNodeList, true)
diff --git a/wcfsetup/install/files/lib/data/user/ignore/UserIgnoreAction.class.php b/wcfsetup/install/files/lib/data/user/ignore/UserIgnoreAction.class.php
index 730c99a8fc3..dd20313cd5e 100644
--- a/wcfsetup/install/files/lib/data/user/ignore/UserIgnoreAction.class.php
+++ b/wcfsetup/install/files/lib/data/user/ignore/UserIgnoreAction.class.php
@@ -255,6 +255,7 @@ protected function getForm(): IFormDocument
                             ->get('wcf.user.ignore.type.hideMessages'),
                     ])
                     ->value($ignore->type ?: 0)
+                    ->required()
                     ->addValidator(new FormFieldValidator('type', function (RadioButtonFormField $formField) {
                         $userProfile = UserProfileRuntimeCache::getInstance()->getObject($this->parameters['userID']);
                         if ($userProfile->getPermission('user.profile.cannotBeIgnored')) {
diff --git a/wcfsetup/install/files/lib/system/form/builder/field/RadioButtonFormField.class.php b/wcfsetup/install/files/lib/system/form/builder/field/RadioButtonFormField.class.php
index 513c0a14207..034407c9f4f 100644
--- a/wcfsetup/install/files/lib/system/form/builder/field/RadioButtonFormField.class.php
+++ b/wcfsetup/install/files/lib/system/form/builder/field/RadioButtonFormField.class.php
@@ -62,11 +62,15 @@ public function supportsNestedOptions()
      */
     public function validate()
     {
-        if (!isset($this->getOptions()[$this->getValue()])) {
-            $this->addValidationError(new FormFieldValidationError(
-                'invalidValue',
-                'wcf.global.form.error.noValidSelection'
-            ));
+        if ($this->isRequired() || $this->getValue() !== '') {
+            if (!isset($this->getOptions()[$this->getValue()])) {
+                $this->addValidationError(
+                    new FormFieldValidationError(
+                        'invalidValue',
+                        'wcf.global.form.error.noValidSelection'
+                    )
+                );
+            }
         }
 
         parent::validate();
diff --git a/wcfsetup/install/files/lib/system/package/plugin/BoxPackageInstallationPlugin.class.php b/wcfsetup/install/files/lib/system/package/plugin/BoxPackageInstallationPlugin.class.php
index e0bb7edbe89..0a15a62a89b 100644
--- a/wcfsetup/install/files/lib/system/package/plugin/BoxPackageInstallationPlugin.class.php
+++ b/wcfsetup/install/files/lib/system/package/plugin/BoxPackageInstallationPlugin.class.php
@@ -560,7 +560,8 @@ protected function addFormFields(IFormDocument $form)
                 ->label('wcf.acp.pip.box.boxType')
                 ->description('wcf.acp.pip.box.boxType.description')
                 ->options(\array_combine(Box::$availableBoxTypes, Box::$availableBoxTypes))
-                ->value('text'),
+                ->value('text')
+                ->required(),
 
             SingleSelectionFormField::create('objectType')
                 ->label('wcf.acp.pip.box.objectType')
diff --git a/wcfsetup/install/files/lib/system/package/plugin/LanguagePackageInstallationPlugin.class.php b/wcfsetup/install/files/lib/system/package/plugin/LanguagePackageInstallationPlugin.class.php
index 824d3f67ed3..0997e7b8b5e 100644
--- a/wcfsetup/install/files/lib/system/package/plugin/LanguagePackageInstallationPlugin.class.php
+++ b/wcfsetup/install/files/lib/system/package/plugin/LanguagePackageInstallationPlugin.class.php
@@ -359,7 +359,8 @@ protected function addFormFields(IFormDocument $form)
                     'selection' => 'wcf.acp.language.item.languageCategoryID.mode.selection',
                     'new' => 'wcf.acp.language.item.languageCategoryID.mode.new',
                 ])
-                ->value('automatic'),
+                ->value('automatic')
+                ->required(),
 
             SingleSelectionFormField::create('languageCategoryID')
                 ->label('wcf.acp.language.item.languageCategoryID')
diff --git a/wcfsetup/install/files/lib/system/package/plugin/PagePackageInstallationPlugin.class.php b/wcfsetup/install/files/lib/system/package/plugin/PagePackageInstallationPlugin.class.php
index 223fb9aebdf..2c5da8a2e4d 100644
--- a/wcfsetup/install/files/lib/system/package/plugin/PagePackageInstallationPlugin.class.php
+++ b/wcfsetup/install/files/lib/system/package/plugin/PagePackageInstallationPlugin.class.php
@@ -489,7 +489,8 @@ protected function addFormFields(IFormDocument $form)
                 ->label('wcf.acp.pip.page.pageType')
                 ->description('wcf.acp.pip.page.pageType.description')
                 ->options(\array_combine(Page::$availablePageTypes, Page::$availablePageTypes))
-                ->addClass('floated'),
+                ->addClass('floated')
+                ->required(),
 
             TextFormField::create('name')
                 ->label('wcf.acp.pip.page.name')
diff --git a/wcfsetup/install/files/lib/system/user/multifactor/TotpMultifactorMethod.class.php b/wcfsetup/install/files/lib/system/user/multifactor/TotpMultifactorMethod.class.php
index 7daf2e1c3c8..7ee1551d206 100644
--- a/wcfsetup/install/files/lib/system/user/multifactor/TotpMultifactorMethod.class.php
+++ b/wcfsetup/install/files/lib/system/user/multifactor/TotpMultifactorMethod.class.php
@@ -280,7 +280,8 @@ public function createAuthenticationForm(IFormDocument $form, Setup $setup): voi
                     ->description('wcf.user.security.multifactor.totp.deviceName.description.auth')
                     ->objectProperty('deviceID')
                     ->options($deviceOptions)
-                    ->value($mostRecentlyUsed['deviceID']),
+                    ->value($mostRecentlyUsed['deviceID'])
+                    ->required(),
             ]);
         }