I didn’t! I just discovered it today while working on fixing a bug. And boy is it awesome! Just hold down the Meta (aka “Super” or “Windows) and Ctrl keys, then scroll. Boom! Note that this only works in a Plasma Wayland session.
We don’t expose this shortcut in the UI right now, so it’s quite hidden and explains why I and probably many others didn’t know about it. We’ll work on improving this.
Adventures in Linux and KDE 
Starting in what version? (Does not work on my system with 5.27.1)
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Hmm weird, I’m on 5.27.2 and it works. I wonder if it only works on Wayland…
Edit: confirmed, it’s Wayland-only. Updated the post.
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FWIW, searching on Zoom in system settings, I find a Zoom under Desktop Effects, which is configured to KWin actions Meta+= and Meta+-, which does work for me.
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Works for me on 5.27.2 Wayland. Very cool feature. Thanks!
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wow, you can zoom in so far that you almost get out on the other side
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Waow, that is cool enough. Glad to know
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It works on X11 too.
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I always use Super and +/-, and Super and 0 to go back to normal zoom level. But this trick with the mouse is also very neat!
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This was one of the first features to demonstrate what is possible on Wayland thanks to input redirection. It was implemented before we had drm support. Back then one could also activate the cube with a mouse shortcut.
That also explains why there’s no GUI to configure.
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I was using Meta+=/Meta+- before, and it worked well, but now when I test it – as well as Ctrl+Meta+Scroll, it only zooms in to the top left corner of my multi-screen setup – not where the mouse is (which is what I remember it should do).
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Doesn’t work very well with a touchpad…
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The zoom level is hard to control with 2-finger scroll on a touchpad: it suddenly zooms all the way in, then changes direction if I keep moving my fingers in the same direction. Using KDE Plasma 5.27.2.
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Yes, it could stand to be improved with a touchpad for sure.
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It works across monitors, too, zooming monitors onto other monitors.
Neat.
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This tiny blog post just completely changed my workflow! I have low-vision so I use desktop zoom constantly. Until now, I had to use a gaming mouse with dedicated buttons mapped to Meta+0/Meta+= to avoid taking my hand off it. It works, but it’s not smooth and if I’m traveling without that mouse, I’m back to the keyboard. This is so much smoother! Thanks! Now I just need to get Wayland on my work laptop.
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That’s great to hear!
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