First, Mozilla has and does assist in the creation of FOSS game engines and tools (Gladius, CubicVR, help to various web ports like JSMESS and various open source game engines, etc.).
Second, even the LGPL shows that absolute avoidance is not always the best thing to do regarding closed-source code. Reality is more complex. Sometimes interoperability with closed-source code is good for everyone including free software.
In particular, a big benefit for free software here is that Unity games can now run on the web, an open platform. Before they required a proprietary plugin that did not work on Linux or BSD, but as JS+WebGL they can run on those platforms. (Yes, the games are proprietary, but visiting websites using proprietary code is basically unavoidable, both on the client and server-side. At least we can do it using FOSS tools now.) So this helps support free software OSes.
A final point, while the Unity engine is a proprietary codebase, they also have lots of code that is FOSS, see their github page. They are also working with even more open source code for the WebGL port, as it uses emscripten.
Parent comment didn't imply the contrary. "stop promoting nonfree software" doesn't mean "stop only promoting nonfree software".
>even the LGPL shows that absolute avoidance is not always the best thing to do regarding closed-source code
If you ask the FSF, the LGPL should really be used as a last resort. Unity is not too common yet (and hopefully will never be as long as it remains proprietary), so I don't see why we should push it forward by helping its integration. Same goes for HTML5's EME. I'd rather have a purely open platform with less features and popularity than a platform with an open base and countless incompatible binary blobs sitting onto it. And even the abomination that EME is would at least be an actual standard.
>Unity engine is a proprietary codebase, they also have lots of code that is FOSS
If you can't build it, it's not worth integrating. The only thing this is good for is making a FOSS alternative (although I guess they keep the important bits secret). I'd be using Google Chrome if "99% open source" was good enough. By using Firefox (though Chromium would be fine if it weren't for the user-hostile features), I precisely want to keep a clean FOSS platform. Conversely, I only use an Android ROM because there's no good alternative, which is not the case for Unity. So I wish they'd keep it out for now.
Even with Unity (and Unreal and others) porting to the web, web browsers remain open, while web content (what ported Unity is) was always non-open (since practically all websites are not FOSS).
I agree with you on the other hand that EME would in fact be a danger to the openness of the web.
>Unity is not related to standards in any way
I know, I mentioned it. I believe a standard at least has some practical positive impact, unlike the integration of a particular closed platform.
>web content was always non-open
It's true that obfuscated JavaScript makes, in a way, a closed platform, but much less so, in my belief, than straight-up binary code (which Unity delivers and EME enables).
I get your overall point, but it just seems a slippery slope...
7 of the top 10 iOS games were developed with Unity, so it is already a really big deal for game developers.
First, build the infrastructure to support amazing things. (Asm.JS, WebGL, WebRTC)
Second, encourage people to spend real money developing for it, however they want to. (Unity 5)
Third, the open source competitors come around. (???)
Examples: Linux, FirefoxOS. On the other hand, no DRM in HTML leads to the platform still being free.
It's easy to integrate proprietary solutions but it's incredibly hard to remove them. IT is way easier to not adopt them in the first place. In that regard, proprietary software is similar to AIDS.
Bananabread? https://developer.mozilla.org/en/demos/detail/bananabread
I don't see it as a sell-out, I see it as competition to the braindead/insulting 'Upgrade your browser' Google notifications and similar nonsense. A sign that Mozilla is very much alive and innovating.