Single stylesheet

Suggest to add a way to use a single Stylesheet for the code and the designer to get a preview through it.

Currently, each widget do have a StyleSheet editor but you cannot tell
Creator/Designer a global one so if you make a new UI files the stylesheet
would already be there.

The way, is to get all preview features in the designer able without have to set manually style in the main component.

Eg:
In our work, we have a designer working on designer tool, we need to keep this graphical feedback for him.
And it seem more clean to set a CSS for all app one time, and have some redefine of style on some components if needed. (As a website work)

I'm my mind, at this time, there is two option to set a single custom stylesheet design:

• The first is to set it inside Tools/Options/Designer/Forms/Print / Preview Configuration as you said, and you can copy all your styles.
• The second way is to set it in the QApplication at the launch of the application. There are several advantages of this way if you have a single style and several .ui or Windows in general. But if you do this way, you d'ont have a preview in designer.
  I was in the middle of this two ways of process. I think it could be great to have a file and link it to the QApplication at the launch and, link of the file inside the Designer to get a preview as feedback.