The Dynamic placeholder was not opening properly in mail template since the wysiwyg OWL conversion. Fix it and also fix the tour that should have detected this error. The tour itself was not running properly. task-3495254 closes odoo/odoo#135275 X-original-commit: df8532cffc74038db0faef36b5f43758e1bbdf43 Signed-off-by: David Monjoie (dmo) <dmo@odoo.com> Signed-off-by: Geelen Sébastien (sge) <sge@odoo.com>