I dunno who comes up with this s..t but it's pretty useless. That plasma widget grouper widget is ridiculous. There's no simple button for it and you can't put it on a panel. There's a keybind setting which is totally useless. So, unless you want it to take a huge part of your desktop it's um...a nono. I quickly made this desktop application for it which does the same (more or less, since you cannot emulate the shortcut nore can you use the damn widget ID) which puts the widgets in a list form. My question is, does anyone happen to know if someone already made such an application, but in widget form? In widget form it could be a lot better. https://imgur.com/a/VeFKEnc

Edit: I managed to use the widget ID...in window form. It works, but a real widget would be better still. Here are a couple of widgets: https://imgur.com/a/mHwc2K1

Of course, you could argue that in windows form it has all the benefits of window settings of course. Nevertheless, still curious if someone came up with it as widget.

So, in case someone wants the desktop file ( goes in ~/.local/share/applications). It can save space for a bunch of widgets and you can pin it to the taskbar if you like.
https://imgur.com/a/BY6Eup0 Change locals and icon according to liking of course.

[Desktop Entry]
Comment[nl_BE]=Grouper
Comment=Grouper
Exec=plasmawindowed org.kde.plasma.grouping
GenericName[nl_BE]=
GenericName=
Icon=headphones
MimeType=
Name[nl_BE]=Grouper
Name=Grouper
NoDisplay=false
Path=
StartupNotify=true
Terminal=false
TerminalOptions=
Type=Application
X-DBUS-ServiceName=
X-DBUS-StartupType=
X-KDE-SubstituteUID=false
X-KDE-Username=

O yeah. This thing requires dragging from widgets into it. In order to do that, open the window>hit alt+F3>more actions>set window in foreground ( dunno what it is in english, anyway, freeze the window in place). Open the widgets panel and start dragging. Once done, untick the window freeze.