diff --git a/htdocs/admin/agenda_reminder.php b/htdocs/admin/agenda_reminder.php
index 9da8f89310a..27c6bbeed73 100644
--- a/htdocs/admin/agenda_reminder.php
+++ b/htdocs/admin/agenda_reminder.php
@@ -187,10 +187,18 @@ print '<td class="center">&nbsp;</td>'."\n";
 print '<td class="right">'."\n";
 
 if (empty($conf->global->AGENDA_REMINDER_BROWSER)) {
-	print '<a href="'.$_SERVER['PHP_SELF'].'?action=set_AGENDA_REMINDER_BROWSER&amp;token='.newToken().'">'.img_picto($langs->trans('Disabled'), 'switch_off').'</a>';
+	if (! getIsHTTPS()) {
+		$langs->load("errors");
+		print img_warning($langs->trans("WarningAvailableOnlyForHTTPSServers"), '', 'valignmiddle size15x').' ';
+	}
+	print '<a class="valignmiddle" href="'.$_SERVER['PHP_SELF'].'?action=set_AGENDA_REMINDER_BROWSER&amp;token='.newToken().'">'.img_picto($langs->trans('Disabled'), 'switch_off').'</a>';
 	print '</td></tr>'."\n";
 } else {
-	print '<a href="'.$_SERVER['PHP_SELF'].'?action=del_AGENDA_REMINDER_BROWSER&amp;token='.newToken().'">'.img_picto($langs->trans('Enabled'), 'switch_on').'</a>';
+	if (! getIsHTTPS()) {
+		$langs->load("errors");
+		print img_warning($langs->trans("WarningAvailableOnlyForHTTPSServers"), '', 'valignmiddle size15x').' ';
+	}
+	print '<a class="valignmiddle" href="'.$_SERVER['PHP_SELF'].'?action=del_AGENDA_REMINDER_BROWSER&amp;token='.newToken().'">'.img_picto($langs->trans('Enabled'), 'switch_on').'</a>';
 	print '</td></tr>'."\n";
 
 	print '<tr class="oddeven">'."\n";
diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index db05f29fe5a..56103e2dc11 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -2897,6 +2897,26 @@ function getUserRemoteIP()
 	return $ip;
 }
 
+/**
+ * Return if we are using a HTTPS connexion
+ * Check HTTPS (no way to be modified by user but may be empty or wrong if user is using a proxy)
+ * Take HTTP_X_FORWARDED_PROTO (defined when using proxy)
+ * Then HTTP_X_FORWARDED_SSL
+ *
+ * @return	boolean		True if user is using HTTPS
+ */
+function getIsHTTPS()
+{
+	$isSecure = false;
+	if (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') {
+		$isSecure = true;
+	}
+	elseif (!empty($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https' || !empty($_SERVER['HTTP_X_FORWARDED_SSL']) && $_SERVER['HTTP_X_FORWARDED_SSL'] == 'on') {
+		$isSecure = true;
+	}
+	return $isSecure;
+}
+
 /**
  * 	Return a country code from IP. Empty string if not found.
  *
diff --git a/htdocs/langs/en_US/errors.lang b/htdocs/langs/en_US/errors.lang
index 501a3005860..9a20094a7aa 100644
--- a/htdocs/langs/en_US/errors.lang
+++ b/htdocs/langs/en_US/errors.lang
@@ -283,3 +283,4 @@ WarningSomeBankTransactionByChequeWereRemovedAfter=Some bank transaction were re
 WarningFailedToAddFileIntoDatabaseIndex=Warning, failed to add file entry into ECM database index table
 WarningTheHiddenOptionIsOn=Warning, the hidden option <b>%s</b> is on.
 WarningCreateSubAccounts=Warning, you can't create directly a sub account, you must create a third party or an user and assign them an accounting code to find them in this list
+WarningAvailableOnlyForHTTPSServers=Available only if using HTTPS secured connection.
\ No newline at end of file
diff --git a/htdocs/theme/eldy/global.inc.php b/htdocs/theme/eldy/global.inc.php
index 2b29bbfd229..6a9cbf112df 100644
--- a/htdocs/theme/eldy/global.inc.php
+++ b/htdocs/theme/eldy/global.inc.php
@@ -769,7 +769,8 @@ span.fa.fa-plus-circle.paddingleft {
     padding-bottom: 2px;
 }
 
-.fa-toggle-on, .fa-toggle-off { font-size: 2em; }
+.size15x { font-size: 1.5em; }
+.fa-toggle-on, .fa-toggle-off, .size2x { font-size: 2em; }
 .websiteselectionsection .fa-toggle-on, .websiteselectionsection .fa-toggle-off,
 .asetresetmodule .fa-toggle-on, .asetresetmodule .fa-toggle-off,
 .tdwebsitesearchresult .fa-toggle-on, .tdwebsitesearchresult .fa-toggle-off
diff --git a/htdocs/theme/md/style.css.php b/htdocs/theme/md/style.css.php
index 01cace5a5e8..550f80216d2 100644
--- a/htdocs/theme/md/style.css.php
+++ b/htdocs/theme/md/style.css.php
@@ -840,7 +840,8 @@ body[class*="colorblind-"] .text-success{
     color: rgb(<?php echo $colortexttitle; ?>) !important;
 }
 
-.fa-toggle-on, .fa-toggle-off { font-size: 2em; }
+.size15x { font-size: 1.5em; }
+.fa-toggle-on, .fa-toggle-off, .size2x { font-size: 2em; }
 .websiteselectionsection .fa-toggle-on, .websiteselectionsection .fa-toggle-off,
 .asetresetmodule .fa-toggle-on, .asetresetmodule .fa-toggle-off {
 	font-size: 1.5em; vertical-align: text-bottom;