I no longer see this problem. No idea what was wrong at the time.

I cannot replicate too.
Where exactly in the UI you have selected the tracks?
Which node in media tree, which view (Details, Art+Details, Art)?

Hi,
I'm still not being able to replicate.

When I noticed the bug, I had something like eight or nine tracks selected. These tracks were not part of the MM library, I was managing a different set.
Then I tested with just two tracks that were in the library, and got the same result.

I am pretty sure there were no other MM windows (or dialogs) open at the time I first noticed the problem; and when I tested after installing the debug version, there definitely were not.

Hi,
I can't replicate it opens Save dialog. How many files you have selected, also maybe it is behind MMW windows (which would be a bug if proven true)?

It's been a while since I last did this, and I'm not 100% sure how it used to behave, but I had success with this before.

I select a number of tracks, right-click, Send To > M3U/XSPF playlist...

and nothing happens. I think it's supposed to give me a File Save dialog for the M3U.
I've installed the debug version and run with DbgView active, and there is no activity in the window except the NC Activate when the context menu closes.

MMW 4.1.16.1836, Windows 10 Home