Ubuntu 26.04 is not compatible with older graphics before OpenGL 3.3

 Are you attempting to install Ubuntu Desktop 26.04 using the image commonly available at https://releases.ubuntu.com/26.04/ubuntu-26.04-desktop-amd64.iso? Me too. You use Rufus to write it to your thumb drive, boot grub, enter the desktop, double click the Installer, and then nothing?

The problem is likely due to your graphics. For anything before Intel Ivy bridge, OpenGL 3.3 doesn't exist. Unfortunately, our friends at Canonical have based their installer on Flutter, which now requires OpenGL 3.3. You can observe this fault using:

journalctl -xe | grep ubuntu

You're looking to find:

"no provider of glBlitFrameBuffer found"

The way around this is shocking simple. Launch Terminal, and:

"sudo su -"

"LIBGL_ALWAYS_SOFTWARE=1 /usr/bin/ubuntu-desktop-bootstrap"

You should be golden.

It's phenomenal that a common and depended on Linux distribution like Ubuntu would not only introduce something as wild as a 3D graphics dependency into its installer process, but they also built it without any considerations for legacy fallback or even a UI message on failure. Bonkers oversight.