I haven't been able to figure out what typeface is causing my MAC to replace it with a light condensed version of Helvetica or Helvetica Neue. But a prime example is this:
It is like this on Firefox, Google Chrome, Safari but only on my MAC. It's bizarre... I have tried clearing history cache all of that.. Installed different version of browsers, on a beta version of firefox right now.. no difference. I have tried to search for a solution, and found nothing.
Also running Maverick, but had the problem before the upgrade.
That is an odd one. Sorry, I'm Mac ignorant, so I can only think of it from a Windows perspective > In the example of Firefox, go to Tools > Options > Content > Fonts and Colors and select your preference. If the font still insists on Helvetica Bold Narrow Elite Classico or whatever, there may be a profile file somewhere that defines general browser settings and that needs deleting. in Windows these browser profiles are in User > AppData > Roaming. Whenever my Firefox goes off the rails- it won't start because it claims it already running. I delete the Firefox profile and all is well- for about another three weeks.
If the above doesn't work > back up your bookmarks, really clean out all versions of all browsers, including applications folders and temp files, install a single browser from a fresh download- and not a beta, and then set your font preference in options.