web player game screen is splited in the firefox browser for mac

Hello, we are making a game of unity web player base of facebook.

In a windows environment when the operation in the firefox browser, is output normally game screen.

However, it is output to the screen as described below in the firefox browser of mac.

We are in order to change to activate the screen size, we use the following code.

Application.ExternalCall("IntegratedPluginCanvas.setResolution", width, height);

In addition, Facebook Canvas Fixed Width, Canvas Fixed Height was set to NO.

The phenomenon is not resolved, is located in the crisis of the current project interruption. Answer thank you to that part.

Unity version : 4.6.8

mac versoin : 10.11.1

firefox version : 43.0.4