Steps to reproduce:

In a fresh install version of Zabbix 7.0 LTS with MYSQL in Ubuntu 22.04. I've created a schedule report to send it weekly via email.

The report it's working fine, but in the email I'm receiving a file named "applicationpdf"... 

Downloading that file and renaming to "something.pdf" I can see that it's a valid PDF.

Result:

Expected:

A file with a correct name and extension (.pdf)