Disabling the Feedback widget on specific devices is easy. As always, find your media in the “Media” section, click on the settings wheel and then go to the“Widgets” section. Under "Feedback widget", you will find the “Show feedback button on devices” option. If you do not wish to show the widget on a specific device, you can just click on it. That device will change color and turn grey: this means the Feedback widget won’t be displayed on that type of device.
Here, for example, we have disabled the Feedback widget on mobile.