I have a problem when add a custom tabs in order view. In new tabs, I have html form:
<form action="<?php echo $block->getUrl('giftvoucheradmin/giftvoucher/addcodetoorder') ?>" method="POST"> // something in here </form>
However, when I click button it alway redirect to admin dashboard. I have try view console and coppy this url and open another window then action work well May I help you? Thank you.