AFAIK, Opera is in no way a proponent of non-profit or open source software. They are a publicly traded for-profit company and their main product is proprietary.
Except that Opera has historically been one of the most significant proponents for open standards, the WHATWG, and opening the web to people without internet access. One should also not forget that Opera is now contributing, and have already landed several patches, to the Chromium and Blink projects.
Yes, but that's certainly a great position to take for a small for-profit selling a proprietary product designed to interpret content primarily written for other software.
Corel probably would have been thrilled to have Adobe make their formats completely open and "standardized" back in the day to reduce the friction of switching products.