Google paid Mozilla Foundation $300 million each year.
Now, I understand, Mozilla Foundation now gets most of its money from Microsoft. Microsoft pays Yahoo. Yahoo pays Mozilla Foundation to make "Yahoo search" (actually mostly Microsoft Bing search) the default search engine in Firefox. Most people don't have the technical knowledge to know how they've been manipulated, or how to restore the default search engine to Google search.
The Thunderbird and SeaMonkey Composer GUIs have been damaged, apparently deliberately. Every time you do a file save, the newer versions of both ask for a new file name, and don't suggest the last one chosen. The damage was reported several months ago, but has not been fixed. Is that another example of Microsoft's Embrace, Extend, Extinguish? People who feel forced away from Thunderbird may choose Microsoft software to replace it. Is that something Microsoft is trying to accomplish?