Fix problem saving wrong value after dynamic update.

extension/Classes/Core/Form/Checkbox.php

@@ -249,9 +249,9 @@ class Checkbox {
             }
 
             // ' ' - This is necessary to correctly align an empty input.
-            $value = ($itemValue[$ii] === '') ? ' ' : $itemValue[$ii];
+            $valueShow = ($itemValue[$ii] === '') ? ' ' : $itemValue[$ii];
 
-            $htmlElement = '<input ' . $attribute . '>' . $value;
+            $htmlElement = '<input ' . $attribute . '>' . $valueShow;
 
             $checkboxLabelId = HelperFormElement::getCheckboxRadioOptionId($formElement[FE_HTML_ID], $ii, HTML_ID_EXTENSION_LABEL);
             $html .= Support::wrapTag("<label class='" . $formElement[FE_BUTTON_CLASS] . "$classActive' id=\"$checkboxLabelId\">",
@@ -345,9 +345,9 @@ class Checkbox {
             }
 
             // '&nbsp;' - This is necessary to correctly align an empty input.
-            $value = ($itemValue[$ii] === '') ? '&nbsp;' : $itemValue[$ii];
+            $valueShow = ($itemValue[$ii] === '') ? '&nbsp;' : $itemValue[$ii];
 
-            $htmlElement = '<input ' . $attribute . '>' . $value;
+            $htmlElement = '<input ' . $attribute . '>' . $valueShow;
 
             $checkboxLabelId = HelperFormElement::getCheckboxRadioOptionId($formElement[FE_HTML_ID], $ii, HTML_ID_EXTENSION_LABEL);
             $htmlElement = Support::wrapTag("<label class=\"$checkboxClass\" $attributeBaseLabel id=\"$checkboxLabelId\">", $htmlElement, true);