[Linux] Find WM_CLASS value for an application

In order to group application windows together, the WMClass and WMInstance attributes have been specified in the Inter-Client Communication Conventions Manual for X server 11.

Long story short, they are two strings that are used to associate application windows to a specific application, they can be set by the application (WMClass) or the user (WMInstance).

They are very useful especially for those applications that are customizations or based on existing tools, which alone would have a different value (eg Java or Eclipse based apps).

Finding the value for a window is as simple as opening a terminal and running:

xprop

Then clicking on the desired window

[Linux] Custom keyboard layout QWERTZ to QWERTY

We already saw how to customize a keyboard layout on Windows, now it's the turn of Linux, using XKB for Xorg.

Remapping keys is as simple as editing a text file. You will find all available layouts under /usr/share/X11/xkb/symbols, you can use them as basis for a new layout or directly edit them.

Pick the layout you want to change (maybe make a backup first), then invert the VALUES ONLY of the two lines containing the lower and uppercase z and y, then save.

You will need to restart X server and the changes will be in effect.

[xorg] Set display to full RGB output

Depending on the monitor being used, the RGB color model supported might be either "Full RGB" or "Limited 16:235"; usually the latter is the one used by TV monitors.

To test the output setting when using xorg, first find out the name of the video connection being used by running:

xrandr

which will list the names and statuses of the available connections. Then manually change the output setting with:

xrandr --output NAME --set "Broadcast RGB" "Full"

Or use "Limited 16:235" instead.

This will not survive a reboot, therefore use whatever method suits you best to force this at every boot, eg by editing/creating the ~/.xprofile file