Any active app (in my case Sketch):
– vs Opera https://cl.ly/5f3d225f91d9 – notice how Opera is behaving
– vs Safari https://cl.ly/6502c975580f – notice how Safari is behaving
– vs Chrome https://cl.ly/341130b3def3 – notice how Chrome is behaving

However, a description of the problem.
Task: minimise the app

1. I'm using at this same time a few apps, in my instance it's Sketch (but can be any other – i.e. some mail app, text app and so on) & Opera.

2. While using them, Sketch which is being used is obviously active, Opera is not active, however it's visible (hidden behind Sketch, which hovers over it)

3. When I want to minimise Opera directly from Sketch (which is active) by clicking on "minimise" yellow button (but it can any button, even of google search) I can't do it.

4. Firstly I have to click wherever on UI of this app to make it active & then minimise it.

I've noticed that it happens only to Opera.

Can I disable this "feature"?

PS. I don't know if the title is accurate, if not, please suggest a correction.