Bathroom sink plug

[Twospaniels]

It’s one of those that goes up and down by using a lever behind the taps.

But how do you get the plug right out to clean it? Or doesn’t it come out?

Push the lever down so it's up as far as it will go then take it out.

No, that doesn’t work.

Something is holding it in there.

In which case, does it unscrew once it's up as far as possible?