Mattermost is also an example of how not to license software, including a promise not to enforce provisions of the license they have chosen. If one needs a promise, one has probably chosen the wrong licensing structure.

Here's a fun one: say I use the MIT binaries, then debug a problem by reading the AGPL source code. What legal position am I in? (If you have an answer for that rhetorical question, by the way, you haven't thought of the problem long enough.)

https://github.com/mattermost/mattermost-server/blob/master/...

They launched exclusively AGPL and then made MIT as a concession after discovering that a number of companies outright ban AGPL and won't pay for it unlike MongoDB, but licensing binaries differently than source code is not something you come across often.