Add sanitation to remove form tags from imported templates

Author: rask

README.md

@@ -222,6 +222,9 @@ and import them into the form admin for specific forms.
 The simplest way is to create a HTML5 file and read its contents. Other
 options include using Twig to render HTML templates.
 
+Remember: WPLF will insert `form` tags on its own, meaning you only have
+to create the markup which sits directly inside the `form` tags.
+
 ### Importing a template into WPLF
 
 Once you're done creating a form template, you need to inform

classes/class-cpt-wplf-form.php

@@ -497,6 +497,10 @@ function maybe_load_imported_template( $post_type, $post ) {
       return;
     }
 
+    // Clear unwanted form tags. WPLF will insert those by itself when rendering a form.
+    $template_content = preg_replace( '%<form ?[^>]*?>%', '', $template_content );
+    $template_content = preg_replace( '%</form>%', '', $template_content );
+
     $this->override_form_template( $template_content, $form_id );
   }