I recently created a new custom email template, when modifying the template the window to modify the information does not appear but it takes me to the top of the screen where the signature fields are. I would like to know if it is an error in the platform and if so if this is corrected in new versions of OJS
This has likely been remedied in future versions of OJS (although it might look differently since new UI improvements have been made). I would recommend upgrading to a more later version if you can, especially because version 3.1 is no longer being supported.