There are many possible reasons why Tangential DE could fail to install.

If the failure occurred during the initial Debian installation, consult the Debian GNU/Linux Installation Guide for information and troubleshooting tips.

If Debian installed successfully and booted up, but then something went wrong with the Tangential DE installation script, you may be able to determine what happened by reviewing the installer log at ~/tande-install.log.

If you want to use Tangential DE as a multi-boot system (for example, to run Windows and Linux on the same machine), you can . . . but it's not tested and that's not really what it's intended for. Scott is only using Tangential DE in virtual machines or as a machine's sole operating system.

If you decide to do it anyway, refer to the base system's guidance. You'll at least need to change the bootloader settings, since Tangential DE has the boot menu disabled (set to a zero-second timeout) by default. Aside from that, it should work . . . probably.

Tangential DE is based on Debian. Its primary software management system is apt, which has been preconfigured with the official repositories (main, contrib, and non-free), the backports repository, and third-party repositories from Mozilla and abraunegg. Additional repositories from Google, Microsoft, and Oracle may be enabled depending on what package sets you selected during installation. The system also includes the Flatpak package manager preconfigured with the Flathub repository.

From the command line, you can manage native packages with apt and Flatpak packages with flatpak.

From the graphical interface, you can manage both native and Flatpak packages with Discover by KDE. The system will notify you if updates are available. You can also manage native packages (but not Flatpack packages) with Synaptic.

Tangential DE is just Debian with some tweaks. Don't think of it as a "true" distribution, but as a customized installation of the one it was built on. You'll keep getting updates as long as the base distribution makes them available. If you want to "revert" to the base system, you can:

• Set the KDE Plasma theme to something other than Tangential Breeze.
• Set the Plymouth bootsplash theme to something other than Tangential.
• Uninstall the "tande-custom" package.

This should leave the system in a working state with nothing but residual settings from Tangential DE, which can be deleted if you come across them or if they cause any issues.

Yes! Tangential DE adds three executable command-line scripts in /usr/bin:

• jfu – EXPERIMENTAL, use with care! – Just f***ing update software from all supported package systems
• tangential-apply-branding – Sets the system name and icon to Tangential DE (runs as an automated process on startup)
• tangential-reset-user-defaults – Re-applies the default user customizations apps (may overwrite some of your preferences!)

That's not a question. And what's wrong with you? Are you some kind of sociopath? I do not understand why people want to go back to the dark ages (heh) of computing. But go ahead, set things up however you want.

The Tangential Breeze theme for Plasma is based on Breeze Twilight, which uses light mode for apps and dark mode for the taskbar and main menu. You can switch over to Breeze Dark for the dark, depressing, sociopathic experience if that's what you like.

Tangential DE will override some apps that stubbornly default to dark mode no matter how the system is set up. These include Blender, GIMP, PyCharm, Shotcut, Visual Studio Code, and others. When possible, I configured them to follow the user's preferences. When that option wasn't available, I set it to use light mode . . . but you can always change it in the app's settings.