Wasted vertical space

I may be wrong about this, but I think that a 3-4 updated ago [when the icons where changed] there was also some adjustment to displaying Actions and Filter. The other possibility is that I've simply changed something in my Mp3tag configuration

Right now my Filter takes twice as much vertical space as toolbar. So I have toolbar with icons, a second empty "toolbar" beneath it and a white Filter box with unnecessary gray area [equally in height to it] on top of it and below it. And that is just an obvious waste of precious space

Also, I have space to show [as a menu under the Actions icon] at the same time only 35 predefined actions [and two signs △ ▽ indicating the existence of more content on this list]; because there is a way too much vertical spacing between them. Somehow the positions [files] in main window are more packed, because I can see also 38 of them [when the toolbar and filter are turned off], so again it it obvious waste of space

This is very likely: if you move the mouse slowly from the label "Filter" to the tag panel above it, the mouse cursor will become an aup-and-down arrow.
In this mode you can adapt the height of the filter section.

Yes, that was the case

So obvious and so dumb of me

But it seems the second issue of too much space between listed actions is something that cannot be defined in Mp3tag itself