http://www.macworld.com/article/164985/2012/01/the_mystery_of_safaris_disappe....nl_newtomac_h_crawlWhy do the YouTube videos play when others don’t? They’re HTML5 files rather than Flash. HTML5 doesn’t require a plug-in
Reader Kevin Mullane has gone on Safari and found himself lost. He writes:
A few weeks ago Safari stopped showing video for some websites. YouTube works, but the highlights videos from mlb.com don’t. My kids use the Mac as well and I’m afraid they messed something up. Any ideas?
My guess is that your kids have been mucking around in Safari’s preferences. Try this: Choose Help -> Installed Plug-ins. Anything appear on the resulting page?
No? Then I have your answer.
Open Safari’s preferences, select the Security preference, and take a gander at the Enable Plug-ins option. Dollars-to-doughnuts, that option is disabled. Switch on that option and the Flash plug-in will be enabled, allowing videos from sites like mlb.com to work as they should.