diff --git a/ChangeLog b/ChangeLog
index 5e1086aed3..f8bfd09277 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -87,6 +87,7 @@ phpMyAdmin - ChangeLog
 - issue #13002 Fixed OpenDocument exports
 - issue #13000 Align NULL values according to the column alignment
 - issue #13021 Show phpMyAdmin errors even with error_reporting set to 0
+- issue #13020 Removed warning about client and server versions mismatch
 
 4.6.6 (2017-01-23)
 - issue #12759 Fix Notice regarding 'Undefined index: old_usergroup'
diff --git a/doc/config.rst b/doc/config.rst
index a0f2a1e33e..f7bc37a17f 100644
--- a/doc/config.rst
+++ b/doc/config.rst
@@ -108,6 +108,10 @@ Basic settings
     :type: boolean
     :default: false
 
+    .. deprecated:: 4.7.0
+
+        This setting was removed as the warning has been removed as well.
+
     A warning is displayed on the main page if there is a difference
     between the MySQL library and server version.
 
diff --git a/index.php b/index.php
index f33a0b44c9..816ad7bf58 100644
--- a/index.php
+++ b/index.php
@@ -574,48 +574,6 @@ if ($server > 0) {
     } // end if
 }
 
-/**
- * Warning about different MySQL library and server version
- * (a difference on the third digit does not count).
- * If someday there is a constant that we can check about mysqlnd,
- * we can use it instead of strpos().
- * If no default server is set, $GLOBALS['dbi'] is not defined yet.
- * We also do not warn if MariaDB is detected, as it has its own version
- * numbering.
- */
-if (isset($GLOBALS['dbi'])
-    && $cfg['ServerLibraryDifference_DisableWarning'] == false
-) {
-    $_client_info = $GLOBALS['dbi']->getClientInfo();
-    if ($server > 0
-        && mb_strpos($_client_info, 'mysqlnd') === false
-        && mb_strpos(PMA_MYSQL_STR_VERSION, 'MariaDB') === false
-        && substr(PMA_MYSQL_CLIENT_API, 0, 3) != substr(
-            PMA_MYSQL_INT_VERSION, 0, 3
-        )
-    ) {
-        trigger_error(
-            Sanitize::sanitize(
-                sprintf(
-                    __(
-                        'Your PHP MySQL library version %s differs from your ' .
-                        'MySQL server version %s. This may cause unpredictable ' .
-                        'behavior.'
-                    ),
-                    $_client_info,
-                    substr(
-                        PMA_MYSQL_STR_VERSION,
-                        0,
-                        strpos(PMA_MYSQL_STR_VERSION . '-', '-')
-                    )
-                )
-            ),
-            E_USER_NOTICE
-        );
-    }
-    unset($_client_info);
-}
-
 /**
  * Warning about Suhosin only if its simulation mode is not enabled
  */
diff --git a/libraries/ThemeManager.php b/libraries/ThemeManager.php
index b80d9673ef..18de556ead 100644
--- a/libraries/ThemeManager.php
+++ b/libraries/ThemeManager.php
@@ -369,7 +369,6 @@ class ThemeManager
         if ($form) {
             $select_box .= '<form name="setTheme" method="get"';
             $select_box .= ' action="index.php" class="disableAjax">';
-            $select_box .=  URL::getHiddenInputs();
         }
 
         $theme_preview_path= './themes.php';
diff --git a/libraries/config.default.php b/libraries/config.default.php
index 841975cfb2..aac14b64a6 100644
--- a/libraries/config.default.php
+++ b/libraries/config.default.php
@@ -61,14 +61,6 @@ $cfg['SuhosinDisableWarning'] = false;
  */
 $cfg['LoginCookieValidityDisableWarning'] = false;
 
-/**
- * Disable the default warning that is displayed if a difference between
- * the MySQL library and server is detected.
- *
- * @global boolean $cfg['['ServerLibraryDifference_DisableWarning']']
- */
-$cfg['ServerLibraryDifference_DisableWarning'] = false;
-
 /**
  * Disable the default warning about MySQL reserved words in column names
  *
diff --git a/libraries/config/messages.inc.php b/libraries/config/messages.inc.php
index cbf973478d..e39ed2ac1b 100644
--- a/libraries/config/messages.inc.php
+++ b/libraries/config/messages.inc.php
@@ -568,12 +568,6 @@ $strConfigPmaNoRelation_DisableWarning_desc = __(
 );
 $strConfigPmaNoRelation_DisableWarning_name
     = __('Missing phpMyAdmin configuration storage tables');
-$strConfigServerLibraryDifference_DisableWarning_desc = __(
-    'Disable the default warning that is displayed if a difference between the '
-    . 'MySQL library and server is detected.'
-);
-$strConfigServerLibraryDifference_DisableWarning_name
-    = __('Server/library difference warning');
 $strConfigReservedWordDisableWarning_desc = __(
     'Disable the default warning that is displayed on the Structure page if column '
     . 'names in a table are reserved MySQL words.'
diff --git a/libraries/config/setup.forms.php b/libraries/config/setup.forms.php
index 2e1d6fb2c3..d308664b9f 100644
--- a/libraries/config/setup.forms.php
+++ b/libraries/config/setup.forms.php
@@ -117,7 +117,6 @@ $forms['Features']['Page_titles'] = array(
     'TitleDatabase',
     'TitleServer');
 $forms['Features']['Warnings'] = array(
-    'ServerLibraryDifference_DisableWarning',
     'PmaNoRelation_DisableWarning',
     'SuhosinDisableWarning',
     'LoginCookieValidityDisableWarning');
diff --git a/libraries/config/user_preferences.forms.php b/libraries/config/user_preferences.forms.php
index 09bb547257..650a2ad718 100644
--- a/libraries/config/user_preferences.forms.php
+++ b/libraries/config/user_preferences.forms.php
@@ -53,7 +53,6 @@ $forms['Features']['Page_titles'] = array(
     'TitleDatabase',
     'TitleServer');
 $forms['Features']['Warnings'] = array(
-    'ServerLibraryDifference_DisableWarning',
     'PmaNoRelation_DisableWarning',
     'SuhosinDisableWarning',
     'LoginCookieValidityDisableWarning',