Tag: linux

Prusaslicer not showing Plater window after background update

If you’re like me you woke up today with Prusaslicer having done an update in the background with Ubuntu’s Flatpak update mechanism hiding somewhere, and your Plater window showing nothing (just a blank area where the 3D field should be).

It took a bit of head scratching, but I realised that Flatpak has its own video drivers for Flatpak software, and these hadn’t been updated.

The fix was simple. Simply type:

flatpak update

In a terminal, and you’ll see something like:

Looking for updates…


        ID                                        Branch          Op      Remote       Download
 1. [ ] org.freedesktop.Platform.GL.default       24.08           i       flathub        1.0 kB / 145.4 MB
 2. [ ] org.freedesktop.Platform.GL.default       24.08extra      i       flathub        1.0 kB / 145.4 MB
 3. [ ] org.freedesktop.Platform.VAAPI.Intel      24.08           i       flathub        1.0 kB / 15.0 MB
 4. [ ] org.freedesktop.Platform.openh264         2.5.1           i       flathub      620.2 kB / 971.4 kB
 5. [ ] org.gnome.Platform.Locale                 48              i       flathub        1.0 kB / 394.5 MB

To which you press “y” to accept the updates. Bingo you should be back up and running.

Fix different scaling between multiple monitors on Ubuntu (22.04+)

If you’re like me, and use a laptop with a 4k screen that is actually far too fine to see, so you run it at 200% UI scaling, you’ll find it frustrating when plugging in external monitors.

This is also an annoyance across all operating systems really, but in Ubuntu, there is a quirk in which a change using the settings menu will apply the same scaling across ALL monitors meaning one monitor will be too small, the other too large.

The good news is there is a pretty simple fix.

At a command line (open terminal) type:

gsettings set org.gnome.mutter experimental-features "['scale-monitor-framebuffer']"

Then log out and in again, you can now individually change your monitor scaling to suit and no longer get frustrated with programs losing their minds when dragged between screens.

Fix Ubuntu 20.04 windows not appearing

I have a few old laptops kicking around that I keep running because with an SSD they’re perfectly fine to keep running. My 10 year old (approx) Samsung laptop is one of these.

Recently I did a fresh install of Ubuntu 20.04 onto this laptop and everything just worked – except for the fact that certain windows, including the Gnome Control Center (gnome-control-center) would open (showing the icon on the left bar) but seemed to quickly move off screen to the right.

I puzzled over this for quite some time trying all sorts of things including launching gnome-control-center from a terminal with -v flag set to see if something was wrong.

I stumbled across a few people talking about windows being off screen from 2014, and methods to bring them back so I tried the following:

  1. Open the control centre so that you see the icon on the left bar, and the red dot next to it showing that it’s running.
  2. Press alt-TAB until you see it highlighted so it’s definitely the window in focus
  3. Hold down alt-F7 and keep holding it, and tap the left arrow. Don’t release these keys yet
  4. Your mouse cursor should disappear now
  5. When you move your mouse left, you should see the window appearing into view
  6. Release alt-F7 and click your mouse when the window is in the middle of the screen

So this will bring the window back, but next time you launch it, it will disappear again. So there’s another problem going on here.

I choose to use the open source Nouveau Xorg video card drivers rather than the closed source, and often buggy on older machines, NVidia drivers, and this laptop has an NVidia card in it (Optimus era). It seems there is a problem, on this laptop at least, that it thinks there’s another display connected to the video output port on the card when I haven’t got anything plugged in.

So while we have the control panel on screen, we’ll go to the “Screen Display” section on the left side, and on the right we’ll choose “Single Display” up the top.

You should now no longer get windows launching off screen or seemingly not launching.