When selecting text in a code block, there is no copy command on the context menu. Command-c will copy, but there is no copy in the context menu.
When selecting text in a code block, there is no copy command on the context menu. Command-c will copy, but there is no copy in the context menu.
Marked 3 now has a Copy menu item in the contextual menu. This will copy as rich text, preserving formatting (e.g. indentation, bold, italics, and colors in code blocks). Copying as plain text does not preserve indentation, so if I decide to support that at some point, it will require a quick HTML->Markdown conversion, which I haven't implemented.
As an aside, I recommend PopClip for all kinds of copy functionality using the mouse.