Thats a good note. I have all of my documentation in markdown (which Microsoft parades on with Github, VSCode, docs.microsoft.com etc) but Copilot cant or wont read these files. I had to pandoc everything over to docx files before it even saw them. Pretty wild.
Also in line with this, Copilot 365 seems to not get how charts work. I asked it with multiple different massaged data sets and it kept giving worse and worse answers even after resetting the chat and data to as simple as possible (think 10 dates, 2 colums of integers) until it ultimately gave me a blank chart. I gave up and asked GPT.