Animations not playing in web build

My animations aren’t playing in a web build. They play correctly in the editor, in a standalone build, and in a mobile build too. The web build shares the same quality settings as the standalone build.

Any idea what might be causing this?

Does anything get written into Player.Log?

No, nothing relevant in the log. I ended up fixing the problem by upgrading to Unity 4.5.2 (from 4.5.0). But it’s strange because the web build was working correctly at one time with 4.5.0, but now it’s not.