<formid="deletion_pseudoform"action="#"th:action="@{'/frontend/image/delete/{id}'(id=${tag})}"th:method="delete"th:tag="${tag}"th:onsubmit="return confirm('Do you really want to delete the imag with tag ' + this.getAttribute('tag') + '?');">
<formth:object="${osChoice}"th:id="request_pseudoform"action="#"th:action="@{'/frontend/container/add'}"th:method="post"th:os="${osChoice}"th:onsubmit="return confirm('You are about to generate a shell with the OS ' + this.getAttribute('osoption') + ' - please be patient after you confirm, as the generation may take a short while.');">
<formid="deletion_pseudoform"action="#"th:action="@{'/frontend/container/delete/{id}'(id=${container.id})}"th:method="delete"th:containerid="${container.id}"th:containerShaSum="${container.imageId}"th:onsubmit="return confirm('Do you really want to delete the container with ID ' + this.getAttribute('containerid') + ' which is attached to the image with checksum ' + this.getAttribute('containerShaSum') + ' ?');">