Obsidian 0.10.2 on Windows 10:
When I copy a PDF file to my vault, I can create a link to that file and display it inside Obsidian, using the [[filename.pdf]] or [pdf](filename.pdf) syntax. However, when I try to do this with an HTML file, i.e. [[filename.html]] or [html](filename.html), then this does not work. Instead of showing the HTML file, as expected, Obsidian creates an empty filename.html.md file and opens that.