Is there a way to hide the green playback cursor without the need to reopen the document? 
It seems the cursor stays visible once it’s activated by pressing the playback button, and is then in the way when going back to editing the score. Even in print mode it occasionally showed up as a black line (as did the note input cursor). However, I can’t reproduce this at the moment (Win10, x64).
There is currently no way to hide the playhead once it has appeared, but we will add this as soon as we can.
OK, great. It’s not a big deal. I was just wondering if I overlooked something.
Is this on the roadmap ?
It would be very nice when making play along videos. The cursor disturbs reading… 
It is indeed already possible: there is an option ‘Show playhead when stopped’ on the Play page of Preferences.
The original request has been implemented, but madsv’s implied question was about hiding the playback cursor during playback…
Ah, sorry, that’s right. No, hiding the playhead during playback is neither currently possible nor planned.
Why not? Your paying customers would be happy. And it seems like a small request IMHO.
Probably because many paying customers do not care.
(Programming requests are seldom “small.”)
We are all in favour of options (to wit, the Engraving Options dialog that has fifty pages and many hundreds of options contained within), but only where they make sense. Adding options, as I have written many times here, isn’t a zero-sum game. They cost money to build, test, localise, document, deploy. They add to the complexity of the software permanently, and every new option adds to the burden of developing future features and fixes, because it now provides not only one behaviour but some greater number of behaviours that can be expected by the user. This complexity also affects the end user, as well, who then has one more option to wade through when they are looking for the option they actually want to find. If we get a groundswell of support for an option that we otherwise don’t plan to add, then of course we are open to reconsidering.