Licensing clarification

[Pelican]

I like this browser and especially like its continued support for what the popular browsers are dropping in favour of mobile phones, namely NPAPI support.

We currently provide a web browser specially designed to protect web media and of late some clients have begged for HTML5 support. So we need to rebuild and it does not look promising to continue with Chromium Embedded Framework (CEF) due their dropping NPAPI, especially when CEF has a problem with HTML5 video licensing/codecs anyway.

I have some developers offering to build in Chromium but it will be a choice of either using Chromium 44 to support NPAPI or use a later version and try to interface NPAPI support through PPAPI.

Now, I do like what Pale Moon has to offer but I suspect that licensing may be a problem, because I am getting the impression that whatever I build Pale Moon resources into has to be made available as source code? Which means that all of our own developments become open-source, or does that just apply to the nobbled, stripped down browser running behind our own gui?

[Moonchild]

The MPL is clear about this part:

3.3. Distribution of a Larger Work

You may create and distribute a Larger Work under terms of Your choice, provided that You also comply with the requirements of this License for the Covered Software. If the Larger Work is a combination of Covered Software with a work governed by one or more Secondary Licenses, and the Covered Software is not Incompatible With Secondary Licenses, this License permits You to additionally distribute such Covered Software under the terms of such Secondary License(s), so that the recipient of the Larger Work may, at their option, further distribute the Covered Software under the terms of either this License or such Secondary License(s).

So, the covered software has to have its source released if modified, meaning the browser part will have to remain MPL compliant, including any specific patches you apply to it to make it compatible for your front-end GUI. Surrounding software does not have to be released under the MPL, but may also not be released under an incompatible Open Source or Commercial license (e.g. GPL requiring waiving of MPL protections on one side, or a custom license restricting disclosure of the MPL-covered code on the other).

The other part of this is that for Officially-branded binaries, our redistribution license applies and inclusion in a larger work is not allowed without an agreement with me in this case:

5. The binaries are not supplied as an integral part of a commercial/non-commercial software package/larger works ("package"). If you wish to do this, you must contact me beforehand to obtain permission and discuss terms. Inclusion in a package will be subject to an individual agreement (either extemporaneous or legalized) which may or may not involve compensation.

If you, however, build from source with unofficial branding or your own branding, then there is no issue as long as the result remains in compliance with the MPL. Mentioning it is based on Pale Moon in that case is appreciated but also not required.