New answers tagged license
In addition to @user64152's answer I have to add one more thing. If along with proprietary you also intend to make a commercial product, you have to buy the Qt Commercial License in order to be able to sell your product.
The community wallpapers are distributed under a CC-BY-SA 3.0 license. Upstream-Name: ubuntu-wallpapers Source: https://launchpad.net/ubuntu-wallpapers Files: * Copyright: 2010-2013 Ubuntu community contributors License: CC-BY-SA 3.0 This information is on disk in /usr/share/doc/ubuntu-wallpapers-trusty/copyright
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