High CPU usage in browser

I noticed high CPU usage if I'm running unity app in Firefox, not sure about other browsers. Even for very simple project (one box and one camera with very simple movement script).

I have Core 2 Duo and one of the CPUs is used up to 100% sometimes, usage jumps from 0 to 100% without any activity. Especially it going up if i'm switching to another tab (just for regular surfing). Such behaviour makes browser usage (with unity game open in one tab) very uncomfortable.

Is it possible to fix it somehow?

There are two things you can do to change CPU load.

One is the "run in background" checkbox in the build settings. If that is checked, you should not get any CPU usage when unity is not in the front window/tab.

The other relevant setting is Application.targetFrameRate. By setting this to a lower value, you can tell Unity not to try to run at any frame rate higher then what you set here, and idle for the remaining time.