I installed wine and now I notice a different font on facebook and a couple of other sites I use a lot. So, how do I get back the default Ubuntu fonts?
Installing wine will also push the "ttf-mscorefonts-installer" package which brings some aditional fonts.
You can remove it without removing wine, but it can negatively affect the look of some applications running from wine.
To remove it, open a terminal and type:
sudo apt-get purge ttf-mscorefonts-installer