What Problem Does Mozilla Public License Solve
Nothing. Like all other free and open source software, software available under the MPL is available for anyone (including individuals and companies) to use for any purpose.
MPL 2.0 FAQ - Mozilla
MPL is a copyleft license that is easy to comply with. You must make the source code for any of your changes available under MPL, but you can combine the MPL software with proprietary code, as long as you keep the MPL code in separate files.
Mozilla Public License 2.0 (MPL-2.0) Explained in Plain English
The MPL is the license for Mozilla Firefox, Mozilla Thunderbird, and most other Mozilla software, but it has been used by others, such as Adobe to license their Flex product line, and The Document Foundation to license LibreOffice 4.0 (also on LGPL 3+).
Mozilla Public License - Wikipedia