Comment by mring33621 3 hours ago
Ok, their license is pretty strange: https://github.com/mattermost/mattermost/blob/master/LICENSE...
MIT for binaries distributed by Mattermost.
But, if you compile it yourself: GNU AGPL v3.0 XOR Paid-for Enterprise License
Then, for some odd reason, they append the text of Apache License Version 2.0!!!
They also have a FAQ: https://docs.mattermost.com/product-overview/faq-license.htm...
Note that they have multiple licenses. This isn't entirely uncommon. The difference licenses apply to different things.
Ooh, I see it now, right in the middle:
"...You are licensed to use the source code in Admin Tools and Configuration Files (server/templates/, server/i18n/, server/public/, webapp/ and all subdirectories thereof) under the Apache License v2.0...."
The frontend parts are explicitly and correctly licensed under the Apache license in the header of the same file.