Gmail will soon block JavaScript files from being uploaded and sent over email. Starting February 13th, you’ll no longer be able to attach .js files as they are increasingly being used as a form of malware. If a user downloads a malicious JavaScript file, hackers can use it to gain access to their PC to steal data or perform other damaging functions.

As reported by Android Police, JavaScript joins .exe, .bat, and .msc as file types that are restricted from being shared as a direct attachment on Gmail. You won’t be able to get around hiding them in compressed forms, such as .zip, either. If you must send a JavaScript file, you can use Google Drive or Google Cloud Storage instead.

Users will receive a warning when they attempt to upload a banned file type, but it is unclear whether they’ll get an alert as well if they’re on the receiving end of said file.