Plasma 5 | Dirk Mittler's Blog

There is a bug in the Wayland Compositor, under Debian Stretch.

One of the facts which I have written about before, is that modern desktop managers will use compositing – i.e. will use hardware-acceleration – to render desktop effects, specifically, when we are only running regular, 2D applications with a GUI. This feature exists with the old KDE 4, under Debian / Jessie, as well as with the new Plasma 5, under Debian / Stretch.

Under Debian / Jessie, this feature is extremely stable. Under Debian / Stretch, it is not yet so.

What will happen under Debian / Stretch, as far as I can make out, is that if an attempt has been made to disable compositing, instead of this succeeding, the desktop-session becomes corrupted, in that black rectangles will display, when we simply open multiple windows / dialogs. AFAICT, This can only be fixed, by rebooting / starting a new user-session.

I became aware of this, when running Steam-based games on the computer I name ‘Plato’. When games run that are heavy on OpenGL / Hardware-Rendering, it’s normal for the game-platform to try to switch compositing off, because often, the hardware-rendering of the game is not compatible with the desktop-compositing. After I have finished my session with Steam, the rendering errors in my desktop manager become noticeable, and Steam does not gain the permissions, to install any system software.

I do not blame this on Steam per se, because I can reproduce this problem by just clicking <Shift>+<Alt>+F12, which used to be the key-combination under KDE 4, that toggled desktop compositing on and off at will. Within seconds, under Plasma 5, this key-combination will also cause the malfunction.

(Updated 12/03/2017 : )

Now, there is a simplistic workaround for me:

Continue reading There is a bug in the Wayland Compositor, under Debian Stretch.

My First Impressions of the New Plasma 5

One of the facts which I’ve been blogging about, is that I have erased Windows from a computer I had, which at the time was named ‘Mithral’, and that I had then installed Debian / Stretch on it, at which point I also changed its name to ‘Plato’. Debian / Stretch is the successor to Debian / Jessie, the latter of which I still have installed on two of my computers.

One of the main differences between the Debian / Stretch and the Debian / Jessie code-repositories is, that the newer Debian / Stretch is based on the desktop manager ‘Plasma 5′ – assuming we choose that desktop-manager – while Debian / Jessie was still based on ‘KDE 4′ as its desktop manager. And so one aspect of my ‘new’ Debian / Stretch system which I’ve been curious about – and anticipating – was how I’ll like Plasma 5 as opposed to KDE 4.

One of the facts which should be noted, is that although Plasma 5 has been altered enough to create major version issues with KDE 4 builds of applications, Plasma is not really that different, finally, from KDE 4.

The developers have focused on simplifying the experience. KDE 4 had almost unlimited options by which the user could fine-tune the appearance of his desktop, while Plasma 5 has reduced the number of settings. And yet I find, I can still do everything under Plasma 5, that I was used to doing under KDE 4. I do not necessarily need to be able to fine-tune, how translucent the Task-Bar is – which under Plasma 5 or KDE 4 specifically is named a ‘Panel’ – while its center-region, where entries exist for applications currently running in user-space, is actually named the ‘Task-Switcher‘. Linux people are sometimes particular about not wanting to seem to be copying the conventions of some other O/S.

Under Linux, we have a variety of methods, to display what processes are occupying the CPU, one of those being the command-line ‘top’, and another being the slightly-more-colorful, but still text-based command ‘htop’. We refer to htop as a ‘Process Viewer’.

One detail which went a bit far for me however, was the degree with which the default Theme – named ‘Breeze’ – made the icons and widgets seem uninteresting. From a package-manager, we can still install a throwback ‘Oxygen’ Theme, the appearance of which is more-similar to how KDE 4 looked. But if we choose the Oxygen Theme, then the default assumption would be that we want our desktop to have a dark look. I actually bypassed this result, by choosing my Look And Feel to be Oxygen, but by choosing my Desktop Theme to be ‘Air’, from the System Settings center. Air is what’s keeping the background-colors of most of my desktop bright-looking.

Also, I always took care to keep wallpapers which I had chosen, and not to allow any switch in Themes to replace those, since a bright-looking wallpaper is also necessary, for obtaining a Desktop Appearance which is bright-looking.

Continue reading My First Impressions of the New Plasma 5

LXDE and Plasma 5 .desktop -Files don’t meet the same requirements.

I’ve just switched a Linux computer of mine from the LXDE to the Plasma 5 desktop managers, because Plasma 5, the successor to KDE 4, is infinitely more-powerful. But then there were some issues with the transition, that may be relevant to my readers, if the readers also wish to switch desktop-managers, on an installed Linux computer.

One fact which I learned, was that even though LXDE and Plasma 5 both use .desktop -Files to launch applications, each system’s .desktop Files are different.

There is a directory named:

‘~/.config/autostart’

In which we find .desktop -Files that are to be run when the user first logs in. And we may find that the initial log-ins don’t run those files:

Also, because the configuration in question is just a set of files, trying to click on these entries in the Plasma 5 settings center does not enable them.

One main reason for which this happens, is the fact that the professional who set up these configuration files, gave the original ones a line that goes like this:

OnlyShowIn=XFCE;LXDE;LXQt;

On my system, this fact was a life-saver, because the LXDE version initially had Compiz installed, which is a fun compositor, but which is not compatible with KDE or Plasma 5. If that had launched, it would have messed up my first attempt to establish a Plasma 5 session.

But there exist other applications which I’d want to have run, even if I’m logging in to Plasma 5, for which reason I used the GUI, to create a Plasma 5 -compatible launcher for the script that updates my version of Flash to the latest version:

And I edited-in a line with a text-editor, which now goes:

OnlyShowIn=KDE;

The exact appearance of the icons here is purely coincidental. But if we wanted to transfer such scripts to:

‘/etc/skel’

Then a big problem for a user like me would be, that scripts which we created in our own home-folders, are likely to contain configuration-details, which will only work for the one user who created them. And so I kept this .desktop -File spartan, to make sure that it will work, regardless of whose home-folder it eventually ends up in.

Dirk

Freshly switched to KDE 4 or Plasma 5, and unable to Browse Network Shares using Dolphin?

I just installed Plasma 5 from the package-manager, on my tower-computer named ‘Plato’, only to find that for some time, I was unable to browse Windows File Shares – i.e. ‘SMB Shares’ – casually, just using the ‘Dolphin’ File Manager. Yet, I was able to mount these shares using ‘Smb4K’, making them visible in my local folders as though there.

Dolphin was showing me an essentially empty set of icons when displaying the Network.

As it turns out, we need to install a package named:

‘kio-extras’

Which will give Dolphin the additional plug-ins it needs, to recognize ‘smb://’ URIs. If our Plasma 5 desktop manager was set up professionally, then the person doing so would know about such details. But when individuals set up KDE or Plasma for the first time, we need to learn such details first-hand.

As an added note, we might find that when we click on the Trash widget in our Panel, which I left just at the right-most end, we may get the error-message to the effect that ‘trash:/’ was a corrupted URL. Yet, from within Dolphin, the trash bin displays just fine.

In my case this was happening, because I did not have Dolphin set up as my default File Management application, in my Plasma 5 Settings, where instead I had an application selected which would have been appropriate to an LXDE desktop, and which does not recognize URIs that begin with ‘trash:/’. Switching this setting to make Dolphin my Default File Manager, fixed this problem.

Dirk