The standards cover the CLR and core library, i.e. the stuff which is replaced in case of an AOT compiler. The .NET framework is an implementation on top of CLR

The standards cover the CLR and core library, i.e. the stuff which is replaced in case of an AOT compiler. The .NET framework is an implementation on top of CLR and the core library, and the Mono project included a version with the intention to be as compatible as possible to .NET, but also an alternative, cross-platform framework, which was/is suitable to build all kinds of applications, including GUIs. Concerning the "blessing" I don't understand why people are less concerned with JDK than with Mono, because the owner of the technology is not exactly known for not enforcing his rights in court (see e.g. https://en.wikipedia.org/wiki/Google_LLC_v._Oracle_America,_Inc https://en.wikipedia.org/wiki/Google_LLC_v._Oracle_America,_....). But fortunately there are limits to copyright when it comes to compatibility.