Mozilla's ace up the sleeve, which I'm sure has been a temptation to them many times - and seems more and more inevitable the more they brand themselves as the privacy browser - is to make ublock origin a default and baked-in feature out of the box.
I see this as an if, not when situation. Google may pull funding immediately if they do so but the surge in users would be extreme, possibly forcing big G to reconsider or lose an ever increasing market share to Bing and DDG.
Maybe DuckDuckGo could pay Mozilla to be Firefox's default search engine and get many more eyeballs on DDG… but if uBlock Origin blocks adverts on DDG, why would DDG pay Mozilla?
I see this as an if, not when situation. Google may pull funding immediately if they do so but the surge in users would be extreme, possibly forcing big G to reconsider or lose an ever increasing market share to Bing and DDG.