"Show only windows from panel's screen" issues on wayland

[stefonarch]

It doesn't work at all on wlroots, showing always every window everywhere, while on kwin it works partially: it can show windows of the screen only but it looks like on the second monitor newly opened windows aren't displayed in it's panel until we restart it.

Moving windows from one to the other monitor needs restarting the panel too to display it in the taskbar.

The need to restart is present also in #2073

[tsujan]

I think it'll also be useful to open 2 reports about multiple active task buttons and no active button under labwc, by describing ways of reproducing them. I can't because I use my workarounds.

I haven't tested under kwin but remember that we had some problems there too (about minimizing by clicking the task button?).

[stefonarch]

I can't see any of the issues I remember in labwc/wlroots, like still one active button if desktop is shown or multiple active buttons together and so on. Maybe you should switch to master to check yourself ;)

On kwin there are some afaik,will check later.

[stefonarch]

While testing it looks like the issue above with windows not shown depends on having two taskbars on two panels, needs checking on X11 too.

[tsujan]

All of the previous issues were present in the master; I checked it first. That was why I edited my workarounds for it ;)