Here it is, based on mock up elements from Qt based apps, I tried to mix and match a few of them to look more or less at home in a very Gtk application, Lollypop.
Description
Description
Related Objects
Related Objects
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I'm making a Widget Factory Mock up, not sure how effective that is but I'll do it anyway. The Headerbar should be the same height as the standard toolbar in Qt apps.
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Thanks. I don't think we need another mockup for this, as the one in T13451 for Blue Ocean already works.