diff --git a/create_classic_poll.php b/create_classic_poll.php
index 920b0ae..fc777c4 100644
--- a/create_classic_poll.php
+++ b/create_classic_poll.php
@@ -40,8 +40,10 @@ if (is_file('bandeaux_local.php')) {
     include_once('bandeaux.php');
 }
 
+$form = unserialize($_SESSION['form']);
+
 // Step 1/4 : error if $_SESSION from info_sondage are not valid
-if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (($config['use_smtp']) ? empty($_SESSION['form']->admin_mail) : false)) {
+if (empty($form->title) || empty($form->admin_name) || (($config['use_smtp']) ? empty($form->admin_mail) : false)) {
     $smarty->assign('title', __('Error', 'Error!'));
     $smarty->assign('error', __('Error', 'You haven\'t filled the first section of the poll creation.'));
     $smarty->display('error.tpl');
@@ -51,10 +53,14 @@ if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (
     $min_expiry_time = $pollService->minExpiryDate();
     $max_expiry_time = $pollService->maxExpiryDate();
 
-    // The poll format is AUTRE (other)
-    if ($_SESSION['form']->format !== 'A') {
-        $_SESSION['form']->format = 'A';
-        $_SESSION['form']->clearChoices();
+    // The poll format is other (A) if we are in this file
+    if (!isset($form->format)) {
+        $form->format = 'A';
+    }
+    // If we come from another format, we need to clear choices
+    if (isset($form->format) && $form->format !== 'A') {
+        $form->format = 'A';
+        $form->clearChoices();
     }
 
     // Step 4 : Data prepare before insert in DB
@@ -69,22 +75,22 @@ if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (
                 $time = mktime(0, 0, 0, $registredate[1], $registredate[0], $registredate[2]);
 
                 if ($time < $min_expiry_time) {
-                    $_SESSION['form']->end_date = $min_expiry_time;
+                    $form->end_date = $min_expiry_time;
                 } elseif ($max_expiry_time < $time) {
-                    $_SESSION['form']->end_date = $max_expiry_time;
+                    $form->end_date = $max_expiry_time;
                 } else {
-                    $_SESSION['form']->end_date = $time;
+                    $form->end_date = $time;
                 }
             }
         }
 
-        if (empty($_SESSION['form']->end_date)) {
+        if (empty($form->end_date)) {
             // By default, expiration date is 6 months after last day
-            $_SESSION['form']->end_date = $max_expiry_time;
+            $form->end_date = $max_expiry_time;
         }
 
         // Insert poll in database
-        $ids = $pollService->createPoll($_SESSION['form']);
+        $ids = $pollService->createPoll($form);
         $poll_id = $ids[0];
         $admin_poll_id = $ids[1];
 
@@ -92,15 +98,15 @@ if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (
         if ($config['use_smtp'] === true) {
             $message = __('Mail', "This is the message you have to send to the people you want to poll. \nNow, you have to send this message to everyone you want to poll.");
             $message .= '<br/><br/>';
-            $message .= Utils::htmlMailEscape($_SESSION['form']->admin_name) . ' ' . __('Mail', 'hast just created a poll called') . ' : "' . Utils::htmlMailEscape($_SESSION['form']->title) . '".<br/>';
+            $message .= Utils::htmlMailEscape($form->admin_name) . ' ' . __('Mail', 'hast just created a poll called') . ' : "' . Utils::htmlMailEscape($form->title) . '".<br/>';
             $message .= sprintf(__('Mail', 'Thanks for filling the poll at the link above') . ' :<br/><br/><a href="%1$s">%1$s</a>', Utils::getUrlSondage($poll_id));
 
             $message_admin = __('Mail', "This message should NOT be sent to the polled people. It is private for the poll's creator.\n\nYou can now modify it at the link above");
             $message_admin .= sprintf(' :<br/><br/><a href="%1$s">%1$s</a>', Utils::getUrlSondage($admin_poll_id, true));
 
-            if ($mailService->isValidEmail($_SESSION['form']->admin_mail)) {
-                $mailService->send($_SESSION['form']->admin_mail, '[' . NOMAPPLICATION . '][' . __('Mail', 'Author\'s message') . '] ' . __('Generic', 'Poll') . ': ' . $_SESSION['form']->title, $message_admin);
-                $mailService->send($_SESSION['form']->admin_mail, '[' . NOMAPPLICATION . '][' . __('Mail', 'For sending to the polled users') . '] ' . __('Generic', 'Poll') . ': ' . $_SESSION['form']->title, $message);
+            if ($mailService->isValidEmail($form->admin_mail)) {
+                $mailService->send($form->admin_mail, '[' . NOMAPPLICATION . '][' . __('Mail', 'Author\'s message') . '] ' . __('Generic', 'Poll') . ': ' . $form->title, $message_admin);
+                $mailService->send($form->admin_mail, '[' . NOMAPPLICATION . '][' . __('Mail', 'For sending to the polled users') . '] ' . __('Generic', 'Poll') . ': ' . $form->title, $message);
             }
         }
 
@@ -112,7 +118,7 @@ if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (
 
         // creation message
         $sessionService->set("Framadate", "messagePollCreated", TRUE);
-        
+
         // Redirect to poll administration
         header('Location:' . Utils::getUrlSondage($admin_poll_id, true));
         exit;
@@ -120,22 +126,22 @@ if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (
     else if (isset($_POST['fin_sondage_autre'])) {
         // Store choices in $_SESSION
         if (isset($_POST['choices'])) {
-            $_SESSION['form']->clearChoices();
+            $form->clearChoices();
             foreach ($_POST['choices'] as $c) {
                 if (!empty($c)) {
                     $c = strip_tags($c);
                     $choice = new Choice($c);
-                    $_SESSION['form']->addChoice($choice);
+                    $form->addChoice($choice);
                 }
             }
         }
 
         // Expiration date is initialised with config parameter. Value will be modified in step 4 if user has defined an other date
-        $_SESSION['form']->end_date = $max_expiry_time;
+        $form->end_date = $max_expiry_time;
 
         // Summary
         $summary = '<ol>';
-        foreach ($_SESSION['form']->getChoices() as $i=>$choice) {
+        foreach ($form->getChoices() as $i=>$choice) {
             preg_match_all('/\[!\[(.*?)\]\((.*?)\)\]\((.*?)\)/', $choice->getName(), $md_a_img); // Markdown [![alt](src)](href)
             preg_match_all('/!\[(.*?)\]\((.*?)\)/', $choice->getName(), $md_img); // Markdown ![alt](src)
             preg_match_all('/\[(.*?)\]\((.*?)\)/', $choice->getName(), $md_a); // Markdown [text](href)
@@ -159,6 +165,8 @@ if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (
 
         $end_date_str = utf8_encode(strftime($date_format['txt_date'], $max_expiry_time)); //textual date
 
+        $_SESSION['form'] = serialize($form);
+
         $smarty->assign('title', __('Step 3', 'Removal date and confirmation (3 on 3)'));
         $smarty->assign('summary', $summary);
         $smarty->assign('end_date_str', $end_date_str);
@@ -186,7 +194,7 @@ if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (
         echo '    </div>' . "\n";
 
         // Fields choices : 5 by default
-        $choices = $_SESSION['form']->getChoices();
+        $choices = $form->getChoices();
         $nb_choices = max(count($choices), 5);
         for ($i = 0; $i < $nb_choices; $i++) {
             $choice = isset($choices[$i]) ? $choices[$i] : new Choice();
@@ -253,4 +261,3 @@ if (empty($_SESSION['form']->title) || empty($_SESSION['form']->admin_name) || (
 
         bandeau_pied();
     }
-
diff --git a/create_date_poll.php b/create_date_poll.php
index 83e0496..487ad70 100644
--- a/create_date_poll.php
+++ b/create_date_poll.php
@@ -44,17 +44,23 @@ if (is_readable('bandeaux_local.php')) {
 $min_expiry_time = $pollService->minExpiryDate();
 $max_expiry_time = $pollService->maxExpiryDate();
 
-// The poll format is DATE
-if ($_SESSION['form']->format !== 'D') {
-    $_SESSION['form']->format = 'D';
-    $_SESSION['form']->clearChoices();
+$form = unserialize($_SESSION['form']);
+
+// The poll format is DATE if we are in this file
+if (!isset($form->format)) {
+    $form->format = 'D';
+}
+// If we come from another format, we need to clear choices
+if (isset($form->format) && $form->format !== 'D') {
+    $form->format = 'D';
+    $form->clearChoices();
 }
 
-if (!isset($_SESSION['form']->title) || !isset($_SESSION['form']->admin_name) || ($config['use_smtp'] && !isset($_SESSION['form']->admin_mail))) {
+if (!isset($form->title) || !isset($form->admin_name) || ($config['use_smtp'] && !isset($form->admin_mail))) {
     $step = 1;
 } else if (!empty($_POST['confirmation'])) {
     $step = 4;
-} else if (empty($_POST['choixheures']) || isset($_SESSION['form']->totalchoixjour)) {
+} else if (empty($_POST['choixheures']) || isset($form->totalchoixjour)) {
     $step = 2;
 } else {
     $step = 3;
@@ -72,25 +78,28 @@ switch ($step) {
         // Step 2/4 : Select dates of the poll
 
         // Prefill form->choices
-        foreach ($_SESSION['form']->getChoices() as $c) {
+        foreach ($form->getChoices() as $c) {
+            /** @var Choice $c */
             $count = 3 - count($c->getSlots());
             for ($i = 0; $i < $count; $i++) {
                 $c->addSlot('');
             }
         }
 
-        $count = 3 - count($_SESSION['form']->getChoices());
+        $count = 3 - count($form->getChoices());
         for ($i = 0; $i < $count; $i++) {
             $c = new Choice('');
             $c->addSlot('');
             $c->addSlot('');
             $c->addSlot('');
-            $_SESSION['form']->addChoice($c);
+            $form->addChoice($c);
         }
 
+        $_SESSION['form'] = serialize($form);
+
         // Display step 2
         $smarty->assign('title', __('Step 2 date', 'Poll dates (2 on 3)'));
-        $smarty->assign('choices', $_SESSION['form']->getChoices());
+        $smarty->assign('choices', $form->getChoices());
         $smarty->assign('error', null);
 
         $smarty->display('create_date_poll_step_2.tpl');
@@ -110,7 +119,7 @@ switch ($step) {
             if (count($_POST['days']) > MAX_SLOTS_PER_POLL) {
                 // Display step 2
                 $smarty->assign('title', __('Step 2 date', 'Poll dates (2 on 3)'));
-                $smarty->assign('choices', $_SESSION['form']->getChoices());
+                $smarty->assign('choices', $form->getChoices());
                 $smarty->assign('error', __f('Error', 'You can\'t select more than %d dates', MAX_SLOTS_PER_POLL));
 
                 $smarty->display('create_date_poll_step_2.tpl');
@@ -118,7 +127,7 @@ switch ($step) {
             }
 
             // Clear previous choices
-            $_SESSION['form']->clearChoices();
+            $form->clearChoices();
 
             // Reorder moments to deal with suppressed dates
             $moments = [];
@@ -138,7 +147,7 @@ switch ($step) {
                     $date = DateTime::createFromFormat(__('Date', 'datetime_parseformat'), $_POST['days'][$i])->setTime(0, 0, 0);
                     $time = $date->getTimestamp();
                     $choice = new Choice($time);
-                    $_SESSION['form']->addChoice($choice);
+                    $form->addChoice($choice);
 
                     $schedules = $inputService->filterArray($moments[$i], FILTER_DEFAULT);
                     for ($j = 0; $j < count($schedules); $j++) {
@@ -148,12 +157,12 @@ switch ($step) {
                     }
                 }
             }
-            $_SESSION['form']->sortChoices();
+            $form->sortChoices();
         }
 
         // Display step 3
         $summary = '<ul>';
-        $choices = $_SESSION['form']->getChoices();
+        $choices = $form->getChoices();
         foreach ($choices as $choice) {
             $summary .= '<li>' . strftime($date_format['txt_full'], $choice->getName());
             $first = true;
@@ -168,6 +177,8 @@ switch ($step) {
 
         $end_date_str = utf8_encode(strftime($date_format['txt_date'], $max_expiry_time)); // textual date
 
+        $_SESSION['form'] = serialize($form);
+
         $smarty->assign('title', __('Step 3', 'Removal date and confirmation (3 on 3)'));
         $smarty->assign('summary', $summary);
         $smarty->assign('end_date_str', $end_date_str);
@@ -190,22 +201,22 @@ switch ($step) {
                 $time = mktime(0, 0, 0, $registredate[1], $registredate[0], $registredate[2]);
 
                 if ($time < $min_expiry_time) {
-                    $_SESSION['form']->end_date = $min_expiry_time;
+                    $form->end_date = $min_expiry_time;
                 } elseif ($max_expiry_time < $time) {
-                    $_SESSION['form']->end_date = $max_expiry_time;
+                    $form->end_date = $max_expiry_time;
                 } else {
-                    $_SESSION['form']->end_date = $time;
+                    $form->end_date = $time;
                 }
             }
         }
 
-        if (empty($_SESSION['form']->end_date)) {
+        if (empty($form->end_date)) {
             // By default, expiration date is 6 months after last day
-            $_SESSION['form']->end_date = $max_expiry_time;
+            $form->end_date = $max_expiry_time;
         }
 
         // Insert poll in database
-        $ids = $pollService->createPoll($_SESSION['form']);
+        $ids = $pollService->createPoll($form);
         $poll_id = $ids[0];
         $admin_poll_id = $ids[1];
 
@@ -213,7 +224,7 @@ switch ($step) {
         if ($config['use_smtp'] === true) {
             $message = __('Mail', "This is the message you have to send to the people you want to poll. \nNow, you have to send this message to everyone you want to poll.");
             $message .= '<br/><br/>';
-            $message .= Utils::htmlEscape($_SESSION['form']->admin_name) . ' ' . __('Mail', 'hast just created a poll called') . ' : "' . Utils::htmlEscape($_SESSION['form']->title) . '".<br/>';
+            $message .= Utils::htmlEscape($form->admin_name) . ' ' . __('Mail', 'hast just created a poll called') . ' : "' . Utils::htmlEscape($form->title) . '".<br/>';
             $message .= __('Mail', 'Thanks for filling the poll at the link above') . ' :<br/><br/><a href="%1$s">%1$s</a>';
 
             $message_admin = __('Mail', "This message should NOT be sent to the polled people. It is private for the poll's creator.\n\nYou can now modify it at the link above");
@@ -222,9 +233,9 @@ switch ($step) {
             $message = sprintf($message, Utils::getUrlSondage($poll_id));
             $message_admin = sprintf($message_admin, Utils::getUrlSondage($admin_poll_id, true));
 
-            if ($mailService->isValidEmail($_SESSION['form']->admin_mail)) {
-                $mailService->send($_SESSION['form']->admin_mail, '[' . NOMAPPLICATION . '][' . __('Mail', 'Author\'s message') . '] ' . __('Generic', 'Poll') . ': ' . Utils::htmlEscape($_SESSION['form']->title), $message_admin);
-                $mailService->send($_SESSION['form']->admin_mail, '[' . NOMAPPLICATION . '][' . __('Mail', 'For sending to the polled users') . '] ' . __('Generic', 'Poll') . ': ' . Utils::htmlEscape($_SESSION['form']->title), $message);
+            if ($mailService->isValidEmail($form->admin_mail)) {
+                $mailService->send($form->admin_mail, '[' . NOMAPPLICATION . '][' . __('Mail', 'Author\'s message') . '] ' . __('Generic', 'Poll') . ': ' . Utils::htmlEscape($form->title), $message_admin);
+                $mailService->send($form->admin_mail, '[' . NOMAPPLICATION . '][' . __('Mail', 'For sending to the polled users') . '] ' . __('Generic', 'Poll') . ': ' . Utils::htmlEscape($form->title), $message);
             }
         }
 
diff --git a/create_poll.php b/create_poll.php
index 179846a..4b269dc 100644
--- a/create_poll.php
+++ b/create_poll.php
@@ -35,9 +35,10 @@ $pollRepository = RepositoryFactory::pollRepository();
 
 /* PAGE */
 /* ---- */
+$form = isset($_SESSION['form']) ? unserialize($_SESSION['form']) : null;
 
-if (!isset($_SESSION['form'])) {
-    $_SESSION['form'] = new Form();
+if ($form === null && !($form instanceof Form)) {
+    $form = new Form();
 }
 
 // Type de sondage
@@ -45,10 +46,10 @@ if (isset($_GET['type']) && $_GET['type'] === 'date' ||
     isset($_POST['type']) && $_POST['type'] === 'date'
 ) {
     $poll_type = 'date';
-    $_SESSION['form']->choix_sondage = $poll_type;
+    $form->choix_sondage = $poll_type;
 } else {
     $poll_type = 'classic';
-    $_SESSION['form']->choix_sondage = $poll_type;
+    $form->choix_sondage = $poll_type;
 }
 
 // We clean the data
@@ -83,20 +84,21 @@ if ($goToStep2) {
     $error_on_customized_url = false;
     $error_on_ValueMax = false;
 
-    $_SESSION['form']->title = $title;
-    $_SESSION['form']->id = $customized_url;
-    $_SESSION['form']->use_customized_url = $use_customized_url;
-    $_SESSION['form']->use_ValueMax = $use_ValueMax;
-    $_SESSION['form']->ValueMax = $ValueMax;
-    $_SESSION['form']->admin_name = $name;
-    $_SESSION['form']->admin_mail = $mail;
-    $_SESSION['form']->description = $description;
-    $_SESSION['form']->editable = $editable;
-    $_SESSION['form']->receiveNewVotes = $receiveNewVotes;
-    $_SESSION['form']->receiveNewComments = $receiveNewComments;
-    $_SESSION['form']->hidden = $hidden;
-    $_SESSION['form']->use_password = ($use_password !== null);
-    $_SESSION['form']->results_publicly_visible = ($results_publicly_visible !== null);
+    $form->title = $title;
+    $form->id = $customized_url;
+    $form->use_customized_url = $use_customized_url;
+    $form->use_ValueMax = $use_ValueMax;
+    $form->ValueMax = $ValueMax;
+    $form->admin_name = $name;
+    $form->admin_mail = $mail;
+    $form->description = $description;
+    $form->editable = $editable;
+    $form->receiveNewVotes = $receiveNewVotes;
+    $form->receiveNewComments = $receiveNewComments;
+    $form->hidden = $hidden;
+    $form->collect_users_mail = $collect_users_mail;
+    $form->use_password = ($use_password !== null);
+    $form->results_publicly_visible = ($results_publicly_visible !== null);
 
     if ($config['use_smtp'] === true && empty($mail)) {
         $error_on_mail = true;
@@ -149,13 +151,15 @@ if ($goToStep2) {
         && !$error_on_password && !$error_on_password_repeat &&!$error_on_ValueMax
     ) {
         // If no errors, we hash the password if needed
-        if ($_SESSION['form']->use_password) {
-            $_SESSION['form']->password_hash = PasswordHasher::hash($password);
+        if ($form->use_password) {
+            $form->password_hash = PasswordHasher::hash($password);
         } else {
-            $_SESSION['form']->password_hash = null;
-            $_SESSION['form']->results_publicly_visible = null;
+            $form->password_hash = null;
+            $form->results_publicly_visible = null;
         }
 
+        $_SESSION['form'] = serialize($form);
+
         if ($goToStep2 === 'date') {
             header('Location:create_date_poll.php');
             exit();
@@ -289,20 +293,21 @@ $smarty->assign('default_to_marldown_editor', $config['markdown_editor_by_defaul
 $smarty->assign('goToStep2', GO_TO_STEP_2);
 
 $smarty->assign('poll_type', $poll_type);
-$smarty->assign('poll_title', Utils::fromPostOrDefault('title', $_SESSION['form']->title));
-$smarty->assign('customized_url', Utils::fromPostOrDefault('customized_url', $_SESSION['form']->id));
-$smarty->assign('use_customized_url', Utils::fromPostOrDefault('use_customized_url', $_SESSION['form']->use_customized_url));
-$smarty->assign('ValueMax', Utils::fromPostOrDefault('ValueMax', $_SESSION['form']->ValueMax));
-$smarty->assign('use_ValueMax', Utils::fromPostOrDefault('use_ValueMax', $_SESSION['form']->use_ValueMax));
-$smarty->assign('poll_description', !empty($_POST['description']) ? $_POST['description'] :  $_SESSION['form']->description);
-$smarty->assign('poll_name', Utils::fromPostOrDefault('name', $_SESSION['form']->admin_name));
-$smarty->assign('poll_mail', Utils::fromPostOrDefault('mail', $_SESSION['form']->admin_mail));
-$smarty->assign('poll_editable', Utils::fromPostOrDefault('editable', $_SESSION['form']->editable));
-$smarty->assign('poll_receiveNewVotes', Utils::fromPostOrDefault('receiveNewVotes', $_SESSION['form']->receiveNewVotes));
-$smarty->assign('poll_receiveNewComments', Utils::fromPostOrDefault('receiveNewComments', $_SESSION['form']->receiveNewComments));
-$smarty->assign('poll_hidden', Utils::fromPostOrDefault('hidden', $_SESSION['form']->hidden));
-$smarty->assign('poll_use_password', Utils::fromPostOrDefault('use_password', $_SESSION['form']->use_password));
-$smarty->assign('poll_results_publicly_visible', Utils::fromPostOrDefault('results_publicly_visible', $_SESSION['form']->results_publicly_visible));
-$smarty->assign('form', $_SESSION['form']);
+$smarty->assign('poll_title', Utils::fromPostOrDefault('title', $form->title));
+$smarty->assign('customized_url', Utils::fromPostOrDefault('customized_url', $form->id));
+$smarty->assign('use_customized_url', Utils::fromPostOrDefault('use_customized_url', $form->use_customized_url));
+$smarty->assign('ValueMax', Utils::fromPostOrDefault('ValueMax', $form->ValueMax));
+$smarty->assign('use_ValueMax', Utils::fromPostOrDefault('use_ValueMax', $form->use_ValueMax));
+$smarty->assign('collect_users_mail', Utils::fromPostOrDefault('collect_users_mail', $form->collect_users_mail));
+$smarty->assign('poll_description', !empty($_POST['description']) ? $_POST['description'] :  $form->description);
+$smarty->assign('poll_name', Utils::fromPostOrDefault('name', $form->admin_name));
+$smarty->assign('poll_mail', Utils::fromPostOrDefault('mail', $form->admin_mail));
+$smarty->assign('poll_editable', Utils::fromPostOrDefault('editable', $form->editable));
+$smarty->assign('poll_receiveNewVotes', Utils::fromPostOrDefault('receiveNewVotes', $form->receiveNewVotes));
+$smarty->assign('poll_receiveNewComments', Utils::fromPostOrDefault('receiveNewComments', $form->receiveNewComments));
+$smarty->assign('poll_hidden', Utils::fromPostOrDefault('hidden', $form->hidden));
+$smarty->assign('poll_use_password', Utils::fromPostOrDefault('use_password', $form->use_password));
+$smarty->assign('poll_results_publicly_visible', Utils::fromPostOrDefault('results_publicly_visible', $form->results_publicly_visible));
+$smarty->assign('form', $form);
 
 $smarty->display('create_poll.tpl');