Etiquette of publishing (continued) research after graduation with an MS degree? Situation
I am soon (maybe...) going to graduate with a thesis-based MS in a technical field. The past year and a half has been incredibly frustrating from a research perspective, as my advisor has insisted on telling me exactly what and how to research, essentially prohibiting me from exploring any of my ideas which are not approved by him.
I believe this is because I unfortunately chose a research area for my MS directly related to his PhD work from some time ago.
I have, for purposes of finishing my degree program, simply acquiesced to his requests in the hopes of finishing as this degree has dragged on for far longer than I want and my current goal is to simply be finished with school officially.
I am currently working full-time (after working in research on campus for ~2.5 years) and have no intent to pursue a PhD in the near future and if so, absolutely not with my current advisor.
Question
I do have personal interest in my research and can see myself exploring my own interests post-graduation, which could result in publishable material. I have no interest in giving my current advisor credit for any of this, should it happen. I also understand he likely would be pretty upset should I actually publish related to my MS work without his involvement.
Are there standard etiquette, unspoken rules, or things to be aware of, within either the academic world or research world which address this situation?
I am posting this anonymously but will be able to clarify
The big issue here is the following: will you need to have your master's thesis advisor write you a letter of recommendation in the near future? If so, then it will be potentially a big problem to publish material from your thesis without his involvement. This will provoke a response, which could be damaging to, for instance, job applications or graduate school admissions. So tread carefully before trying to publish the MS work.

However, since your advisor has proscribed work in other directions as part of your thesis, you could certainly explore those on your own. In such a case—since it isn't an outgrowth of your thesis work, but essentially a "parallel" work, you wouldn't need to share co-author credit with him. This is especially true if you write the paper and direct the research yourself; in such cases, he has no real claim to being on the paper.