The subject of xdg runtime dir not set in the environment encompasses a wide range of important elements. terminology - What does XDG stand for? The XDG Base Directory Specification standardizes best practices for which folders a user-scoped programs may write to. What does XDG stand for, what's the story behind the name? How can I set which application is launched by 'xdg-open'?. The xdg-mime commands are exactly what I needed! I'm running Manjaro-i3, so I don't have a desktop environment at all.
(and the GConf and update-alternatives answers above don't apply) google chrome - What is xdg-open? Additionally, the xdg-open is used to open a url or file in the your preferred program. Use xdg-open --manual to learn more. xdg-open opens a file or URL in the user's preferred application. If a URL is provided the URL will be opened in the user's preferred web browser.
xdg-open supports file, ftp, http and ... Where should the XDG_CONFIG_HOME variable be defined?. The XDG specification talks about the XDG_CONFIG_HOME variable, but does not specify where it should be defined.

It's important to note that, should we define it in /etc/X11/Xsession, or is it the window manager's config file ... What are the step to move all your dotfiles into XDG directories?. This post aims to help users who desi... command line - What is XDG_RUNTIME_DIR? 11 XDG_RUNTIME_DIR is an environment variable set in your X Windows context, so that programs can find things.
You (neo) have set up the graphics context. By trying to run evince as root, you have entered the condition where a user (root) is trying to access another user's (neo) display. This is regarded as a Bad Thing. How to set XDG_RUNTIME_DIR - Ask Ubuntu.
$XDG_RUNTIME_DIR is not well set on my computer and this causes upstart to write PID files to my home folder. May I know what it should be and where to set it? 23.10 - Slow snap startup caused by an xdg-desktop-portal service (xdg ....
Update: With xdg-desktop-portal masked I don't have slowness issues at boot but it causes other problems -- at least one I'm aware of. In Firefox (snap), when I trying to insert a PDF into OneNote it doesn't work. The local file picker simply doesn't show up.

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