Mailto link not copying body of email on Chromebook

I'm generating a mailto: link that also contains the body of an email. I'm opening the link using JavaScript to launch the mailto: client of the OS. On Chromebooks the link opens Gmail with the email address, but not the body of the email. This is the link:

var MailToLink = 'mailto:test@test.com?subject=Test%20Email%20Subject&body=Great,%20the%20mailto%20protocol%20works%20and%20you%27re%20good%20to%20go.%20Good%20luck.'

This is the line I use to open the link: window.open(MailToLink, '_blank');

It works just fine on Windows 10 OS with Thunderbird and Gmail for Android.

Is there something I need to change for Chromebooks?

from Mailto link not copying body of email on Chromebook