Recently I've become quite interested in Coptic language. I've done some research and found that, although the language is more or less dead and not used for day-to-day communication any more, there are still people who learn it and use it. Egyptologists use it for insights into Ancient Egyptian that it's most closely related to, some Coptic Christian churches use it liturgically, there are quite a few religious and philosophical texts surviving in it, plus some Egyptian nationalists think of reconstructing it similarly to how Eliezer Ben-Yehuda reconstructed ancient Hebrew and use it in daily life.
The problem is, however, that Coptic didn't ever have a common literally norm and there are a lot of dialects that differ from one another considerably. The learning aids one can find in the internet are based on different dialects and instead of helping one learn by complimenting one another they only confuse one. This makes it unclear as to how to approach learning the language.
At least for a beginner it is essential to be able to focus on one dialect at a time, maybe broadening one's knowledge into other dialects later. As far as I was able to understand, the most widespread dialects are Sahidic which has the largest corpus of texts and Boharic, or so-called Greco-Boharic, the variant of language used by Coptic Christan churches and taught to their priests. Which of them would make the most sense to start learning the language by?