diff --git a/include/errors/class_SimplePluginCheckError.inc b/include/errors/class_SimplePluginCheckError.inc
index dff0535ef99f4cebaf06ecc8f02b567641d04c8b..ee906dad927bcade11d44da6cb839f2b78189c0d 100644
--- a/include/errors/class_SimplePluginCheckError.inc
+++ b/include/errors/class_SimplePluginCheckError.inc
@@ -30,7 +30,7 @@ class SimplePluginCheckError extends SimplePluginError
    *
    * \return HTML string
    */
-  static public function invalidValue(string $error): string
+  static public function invalidValue (string $error): string
   {
     return sprintf(
       '<b>%s</b> %s',
diff --git a/include/simpleplugin/attributes/class_IntAttribute.inc b/include/simpleplugin/attributes/class_IntAttribute.inc
index b5218747a7434534ad7d851085c9da2cf8a43e87..e3252a8ccdb3166f3fb961935cc8102e69820074 100644
--- a/include/simpleplugin/attributes/class_IntAttribute.inc
+++ b/include/simpleplugin/attributes/class_IntAttribute.inc
@@ -45,7 +45,7 @@ class IntAttribute extends Attribute
     $this->max      = ($max === FALSE ? FALSE : $this->inputValue($max));
   }
 
-  public function getExample (): ?string
+  public function getExample ()
   {
     if (($this->min !== FALSE) && ($this->max !== FALSE)) {
       return sprintf(_('An integer between %d and %d'), $this->min, $this->max);
@@ -170,7 +170,7 @@ class FloatAttribute extends IntAttribute
     $this->step = 0.01;
   }
 
-  public function getExample (): ?string
+  public function getExample ()
   {
     if (($this->min !== FALSE) && ($this->max !== FALSE)) {
       return sprintf(_('A float between %f and %f'),  $this->min, $this->max);
diff --git a/include/simpleplugin/attributes/class_StringAttribute.inc b/include/simpleplugin/attributes/class_StringAttribute.inc
index 74a73ee93939e489fdad6c4e7de4d4f0a6020954..4a3aec48e70d9a524a10b0ad8ac6726405597046 100644
--- a/include/simpleplugin/attributes/class_StringAttribute.inc
+++ b/include/simpleplugin/attributes/class_StringAttribute.inc
@@ -53,7 +53,7 @@ class StringAttribute extends Attribute
     $this->example = $example;
   }
 
-  public function getExample (): ?string
+  public function getExample ()
   {
     return $this->example;
   }
diff --git a/include/simpleplugin/class_Attribute.inc b/include/simpleplugin/class_Attribute.inc
index ebf5815a6b0a13a26de1ac02dd4dd4b4723b383c..e03f20ef6a1bfe25ac8ee4eaf5681a8a9ce235fd 100644
--- a/include/simpleplugin/class_Attribute.inc
+++ b/include/simpleplugin/class_Attribute.inc
@@ -121,7 +121,11 @@ class Attribute
     $this->manageAttributes($this->getValue());
   }
 
-  function getParent(): ?simplePlugin
+  /*! \brief Get parent plugin instance, if any
+   *
+   * \return simplePlugin|null
+   */
+  function getParent ()
   {
     return $this->plugin;
   }
@@ -172,7 +176,11 @@ class Attribute
     return $this->inLdap;
   }
 
-  public function getExample (): ?string
+  /*! \brief Get an example value
+   *
+   * \return string|null
+   */
+  public function getExample ()
   {
     return NULL;
   }
diff --git a/include/simpleplugin/class_simplePlugin.inc b/include/simpleplugin/class_simplePlugin.inc
index b05acf8e0e42c2a54e7e46cebe8208cab22074f8..0baa4b3098a2d14ab3066a0fab07e3e3df82f9e6 100644
--- a/include/simpleplugin/class_simplePlugin.inc
+++ b/include/simpleplugin/class_simplePlugin.inc
@@ -1468,7 +1468,6 @@ class simplePlugin implements SimpleTab
       default:
         trigger_error(sprintf('Invalid %s event type given: "%s"! Valid types are: add, modify, remove.', strtolower($when), $mode));
         return [];
-        break;
     }
   }