I accidentally pattern into Notepad++ and it became out as fully operational xml. />/>/>
So, i repeated this with few different patterns (CTRL+F4 to copy and in Np++ CTRL-V to paste), started a new song to test it out (copied xml from Np++ and pasted it into pattern with CTRL+F5) and it worked somewhat fine. It pastes the exact same structure, so any differences in groups/tracks/columns/instrument numbers and you’re basically screwed. But if your tracks and instruments are identical, copying works fine.
Edit: added CTRL+ to F4 and F5.
Edit 2: Works for block (ALT+ F4/F5) and track (SHIFT+ F4/F5) copying, too.