"Dependent" suggests a necessity is being fulfilled, and that's the point of my comment. We're past necessity. Both Mozilla and Wikimedia are already bringing in several times over the amount of cash they need to operate.
AIUI, both organizations have plenty of worthwhile projects which are constrained by available funding. They're not just maintaining a web browser + hosting an encyclopedia.
Of course, this is not to say that funding the Archive isn't also important.
Say Wikimedia would become dependent on the donations of a company, that company could technically force them to publish misleading information.
In regards to mozilla they are currently not financially independent.
Most of their money comes from google (in exchange google is the default search engine).