Psy-Q's Braindump

In some situations, you may end up with emoji displaying in color in GTK applications but not in Qt ones (such as Kate, Konsole, etc.)

If you’re sure you have a color emoji font installed (e.g. fonts-noto-color-emoji) and still get most emoji in black and white, it might be because your system default font provides black and white emoji already. The color font further down the line is never matched so you get black and white emoji instead.

The cause of this problem is very complicated but the solution is easy: Slap this into your /etc/fonts/local.conf (and maybe run fc-cache -f as root):

<?xml version='1.0'?>
<!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
<fontconfig>
  <alias>
   <family>sans-serif</family>
   <prefer>
    <family>Noto Sans</family>
    <family>Noto Color Emoji</family>
    <family>Noto Emoji</family>
    <family>DejaVu Sans</family>
   </prefer>
  </alias>
  <alias>
   <family>serif</family>
   <prefer>
    <family>Noto Serif</family>
    <family>Noto Color Emoji</family>
    <family>Noto Emoji</family>
    <family>DejaVu Serif</family>
   </prefer>
  </alias>
  <alias>
   <family>monospace</family>
   <prefer>
    <family>Noto Mono</family>
    <family>Noto Color Emoji</family>
    <family>Noto Emoji</family>
   </prefer>
  </alias>
  <dir>/usr/local/share/fonts</dir>
</fontconfig>Code language: HTML, XML (xml)

Shamelessly stolen from various sources.

If you stream audio in various formats from MPD to music clients, you may have run into a problem. Sometimes audio might simply go silent on a track change even though your MPD client says it’s playing the next song. This might actually have something to do with your player: some players don’t deal with audio frequency or resolution changes well. If you have audio in various resolutions and bitrates, this can trigger such a silence.

There’s one way to work around this, forcing your audio output to always have the same frequency and resolution via the format option:

audio_output {
  type        "httpd"
  name        "Whatever"
  encoder     "lame"
  port        "8001"
  bitrate     "320"     
  max_clients "8"    
  mixer_type  "software"
  format      "44100:16:2"
  always_on   "yes"
}Code language: JavaScript (javascript)

The always_on option may help as well with especially picky audio players. It produces a constant stream of silence so that there is always a bitstream for clients to receive.

A problem with this approach is of course that if you have a lot of audio in e.g. 48 KHz and 24-bit, the resulting stream will be downsampled. But you can try using e.g. 48000:24:2 in this case. I’m not sure if upsampling 44.1 KHz content to 48 KHz might introduce audible artifacting; I certainly can’t hear it.

Thanks to Neo-Desktop on GitHub for digging up my old gist about this issue and testing the workaround.

For several months now, my keyboard layout would reset to English (US) every time I log into Plasma. I’ve tried every possible way to force it to my preferred layout, EurKey, but nothing worked: xorg.conf snippets, localectl configurations, it seemed Plasma simply ignored these settings.

At first I blamed Plasma, but it’s innocent: The problem is Zoom! The Zoom package contains an unnecessary dependency on IBus, at least in the RPM that Zoom packages for openSUSE. IBus comes with its own keyboard handling and is useful if you want to type text in Chinese, Japanese, Korean or other languages using non-Latin characters. But it also means that if you don’t configure IBus, your Plasma session will start with English (US) no matter what XKB keyboard layout you have set in Plasma.

The solution, at least until Zoom fixes their package, is to tell IBus to use your XKB keyboard layout. Right-click the IBus widget in the system tray and go to advanced preferences:

Here, select “use system keyboard layout”. This will force IBus to use whatever is set via XKB.

My RX 580 has been giving me trouble recently. There is now an audible clicking when its fans spin up from zero RPM, and unfortunately, this happens a lot in desktop use.

Not wanting to invest in an aftermarket fan just yet, I looked for ways to manage the fan RPM curves while overriding the GPU BIOS and I found amdgpu-fan.

I prefer this to the other solutions out there for a few reasons:

• Doesn’t need (or even have) a GUI
• It’s just a small Python script
• The config file format uses nice human-readable numbers (percentages, not absolute values)
• The file’s a simple bit of YAML
• The tool seems to rather smoothly calculate curves between the stop points you configure

To prevent the clicking noise when the fan engages, I set it to run at 35% RPM even as a baseline, and not ramp up until the GPU hits 60 degrees. At this setting, I can’t hear the fans during desktop use; goal accomplished.

My config for an XFX Radeon RX 580 GTS XXX Edition looks like this:

speed_matrix:
- [0, 35]
- [30, 35]
- [45, 35]
- [50, 35]
- [60, 40]
- [70, 45]
- [75, 52]
- [80, 78]
- [92, 100]Code language: YAML (yaml)

I also slapped a systemd service into /etc/systemd/system/amdgpu-fan.service to activate on boot:

[Unit]
Description=amdgpu fan controller

[Service]
ExecStart=/usr/local/bin/amdgpu-fan
Restart=always

[Install]
WantedBy=default.targetCode language: TOML, also INI (ini)

So far, I’m happy!

There’s a reason for the very specific title: It seems this feature is configured a little differently on Tumbleweed than on openSUSE Leap and I haven’t found any up-to-date information on this. So I’m writing this down as a note to myself.

A default Plasma desktop will use kwallet to save passwords for various desktop services (802.11x passwords, Nextcloud/ownCloud logins, SSH key passphrases, etc.). This can get inconvenient when e.g. Nextcloud wants to access the Internet, but the wallet isn’t unlocked yet, so Plasma can’t decrypt the WLAN PSK.

One solution is to:

• Make your kwallet password the same as your user password
• Ensure kwallet’s default wallet is called “kwallet” and that it’s the one that contains the keys you want unlocked on login
• Make sure this wallet is using Blowfish encryption (this will not work in gnupg mode)
• Install the require PAM modules

The package on openSUSE Tumbleweed is “pam_kwallet”, so:

sudo zypper in pam_kwallet

Log out from your desktop session, log back in and it should immediately work. In the past, you would have had to add the pam modules to /etc/pam.d/common-session or /etc/pam.d/sddm,but this is now done automatically.

The elegance of this is that you can still store more precious passwords in a separate wallet in Wallet Manager (just call that one something other than “kwallet”). That wallet can then be set to decrypt only on demand. This should save a lot of passphrase typing on a typical day.