I'm really surprised by the naysayers in this thread. Mozilla is a not-for-profit. The largest and most influential when it comes to action on the web given their footprint directly in-front of the users.
You're complaining about lack of some edge-css features, silly bugs that have been open for a long time, and the fact that they may be chasing down some avenues that yield little fruit.
But, the web I envision without them is one that I do not want any part of. While I switched and used Chrome (for the tools), lately, the only browser vendor that I trust is Mozilla. I switched back to FF, donated, and decided to start dipping into their code/docs to see if I can help out.
While certainly not perfect, they are the company that we should be supporting. Not necessarily financially, but by being advocates, code/doc junkies and designers.
Here's to Mozilla and here's to 2014. Congrats!