At present, if a popover is active, using Alt-Tab or clicking on a different window closes the popover.
Would it be possible for the poover to stay open, even when temporarily switching to another window? When I’m on a laptop, I need all the screen real estate, and when I’m entering lyrics I’m often using Alt-Tab to toggle between Dorico and, say, a web page.
Thanks for the consideration.
I remember this has already been asked a long while ago, and I think I remember that for boring technical reasons, this was not possible… I’ll try to find that thread if I have some time 
Yes, the nature of popovers is that they are semi-modal, that is to say that they close when the app loses focus. I’m sure we could change this given sufficient will, but I don’t think we want to.
Just putting my two cents in, I’m constantly switching back to my browser to look at lyrics while I’m entering them and I switch back to Dorico and immediately start typing only to realise that the popover has been closed. It’s only a minor quibble, and maybe a sign I should get better at memorising the lyrics I’m working with, but if you find yourselves with nothing better to do at the office I’d love to see this implemented one day. 
In Dorico 3, you can now copy and paste lyrics directly into the lyrics popover - in case that helps with your workflow? You would only need to hyphenate the syllables as required, then copy the whole line once, then paste one syllable at a time. See here