I know the keyboard-shortcut for hiding the active window. Is there also a keyboard-shortcut for hiding the inactive windows (only on the current desktop) while the active window is still there?
If not, there should be such a shortcut.
GNOME Shell’s workflow primarily involves switching workspaces instead of minimizing / reopening windows. The equivalent of what you’re looking for would be Super + Shift + PgUp or PgDn, which moves the currently active window to the next/previous workspace and switches to that workspace at the same time.
Unfortunately this is no alternative option because of 2 reasons:
The suggested shortcut moves the active window to another workspace, but this could have other windows again, so you have the same problem and you are moving the window from workspace to workspace, searching for a workspace, where this window in the only one.
This is no option, if you want to look at only this one window (for avoiding the clutter) for a certain amount of time, but later you still want to use it with the other windows on that same workspace.
E.g. you have 4 windows on one workspace, that are all related to one single project / worktask. For a short time you wand to focus only one of them, to not be distracted. But later you still want to use all 4 windows for that project / task without first moving a window to other workspaces and then moving it back again.
See what I mean? This is no solution for this problem.
By the way:
as long as it doen’t break the paradigm of the software, the software should adapt to the user, not the opposite way.
And an additional keyboard-shortcut for hiding the background-windows of the current screen doesn’t break anything for any user. It only gives some users an additional shortcut, but who doesn’t need it, has exactly the same user-experience as today.
And the concept of hiding windows is already part of Gnome, but only for the active window (super+H). So an additional shortcut for hiding the inactive windows on the current screen (e.g. Super+shift+H) is the next logical step.
Just maximize that window
That’s a workaround as long as this feature is missing. But it is not the perfect solution, but in many windows you don’t want to use it fullscreen, e.g. because that means you have way too much whitespace.