Issue #2794289 by GoZ, droplet, chiranjeeb2410: add `type=button` to toolbar tab buttons

core/modules/contextual/contextual.module

@@ -36,6 +36,7 @@ function contextual_toolbar() {
       '#attributes' => [
         'class' => ['toolbar-icon', 'toolbar-icon-edit'],
         'aria-pressed' => 'false',
+        'type' => 'button',
       ],
     ],
     '#wrapper_attributes' => [

core/modules/tour/tour.module

@@ -54,6 +54,7 @@ function tour_toolbar() {
       '#attributes' => [
         'class' => ['toolbar-icon', 'toolbar-icon-help'],
         'aria-pressed' => 'false',
+        'type' => 'button',
       ],
     ],
     '#wrapper_attributes' => [