Webform email twig template questions What is the correct syntax to test if a file has been uploaded in a webform in a twig email template?

For a text area, {% if webform_token('[webform_submission:values:question_text_area:value]', webform_submission) %} works fine but to test if a file has been uploaded, {% if webform_token('[webform_submission:values:join_a_file:value]', webform_submission) %} does not work.

Also, when there's a file uploaded, I want to display in the email only the title of the file ... {{ webform_token('[webform_submission:values:join_a_file:delta:format:value]', webform_submission) }} works but it outputs a link to that file. Is it possible to just have the text of the file name?

Thanks!
That is a great question. 

Getting just the filename is not currently supported but you can pull the file's URL using [webform_submission:values:join_a_file:delta:format:url]

The current list of supported formats for uploaded files is here. I created a ticket to 
add machine name to element submission display formats so that this information is exposed to site builder.

If you need just the file name, please create a new ticket in the Webform module's issue queue.