That would violate point 5 of the Mozilla Manifesto.
They can interpret that however they want. For example, you can always "shape the Internet and [your] own experiences on it", including removing any blocking, adding things they remove, etc... just get the source code for Firefox and make all the changes you want.
It's all a bunch of vague marketing doublespeak anyway, with around as much power over what Mozilla does as the US constitution has on the US government.
They can interpret that however they want. For example, you can always "shape the Internet and [your] own experiences on it", including removing any blocking, adding things they remove, etc... just get the source code for Firefox and make all the changes you want.
It's all a bunch of vague marketing doublespeak anyway, with around as much power over what Mozilla does as the US constitution has on the US government.