diff --git a/src/Forms/Controls/SubmitButton.php b/src/Forms/Controls/SubmitButton.php
index 06cf9291b..a2858ccb1 100644
--- a/src/Forms/Controls/SubmitButton.php
+++ b/src/Forms/Controls/SubmitButton.php
@@ -73,7 +73,7 @@ public function setValidationScope(?iterable $scope)
 			$this->validationScope = [];
 			foreach ($scope ?: [] as $control) {
 				if (!$control instanceof Nette\Forms\Container && !$control instanceof Nette\Forms\Control) {
-					throw new Nette\InvalidArgumentException('Validation scope accepts only Nette\Forms\Container or Nette\Forms\IControl instances.');
+					throw new Nette\InvalidArgumentException('Validation scope accepts only Nette\Forms\Container or Nette\Forms\Control instances.');
 				}
 				$this->validationScope[] = $control;
 			}
diff --git a/src/Forms/Rendering/DefaultFormRenderer.php b/src/Forms/Rendering/DefaultFormRenderer.php
index 57d6c54e0..93e5e1dc6 100644
--- a/src/Forms/Rendering/DefaultFormRenderer.php
+++ b/src/Forms/Rendering/DefaultFormRenderer.php
@@ -386,7 +386,7 @@ public function renderPairMulti(array $controls): string
 		$s = [];
 		foreach ($controls as $control) {
 			if (!$control instanceof Nette\Forms\Control) {
-				throw new Nette\InvalidArgumentException('Argument must be array of Nette\Forms\IControl instances.');
+				throw new Nette\InvalidArgumentException('Argument must be array of Nette\Forms\Control instances.');
 			}
 			$description = $control->getOption('description');
 			if ($description instanceof HtmlStringable) {
diff --git a/src/compatibility.php b/src/compatibility.php
index 84d758ef9..dd9c45ee5 100644
--- a/src/compatibility.php
+++ b/src/compatibility.php
@@ -11,7 +11,7 @@
 
 if (false) {
 	/** @deprecated use Nette\Forms\Control */
-	class IControl extends Control
+	interface IControl extends Control
 	{
 	}
 } elseif (!interface_exists(IControl::class)) {
@@ -20,7 +20,7 @@ class_alias(Control::class, IControl::class);
 
 if (false) {
 	/** @deprecated use Nette\Forms\FormRenderer */
-	class IFormRenderer extends FormRenderer
+	interface IFormRenderer extends FormRenderer
 	{
 	}
 } elseif (!interface_exists(IFormRenderer::class)) {
@@ -29,7 +29,7 @@ class_alias(FormRenderer::class, IFormRenderer::class);
 
 if (false) {
 	/** @deprecated use Nette\Forms\SubmitterControl */
-	class ISubmitterControl extends SubmitterControl
+	interface ISubmitterControl extends SubmitterControl
 	{
 	}
 } elseif (!interface_exists(ISubmitterControl::class)) {