How to Open JPEG XL Images on Linux

Mint, Ubuntu and Debian-based

Go to the JPEG XL's GitHub releases.

Download the packages for your distribution. I use Linux Mint, so I'll choose the latest Ubuntu.

Move the file to a separate folder and extract.

Open the terminal in the current folder.

Install the packages with this command.

sudo dpkg -i *deb

Open any JXL file.

Assign Image Viewer as the default application.

You can now open JXL images.

gThumb

Alternatively, you can install gThumb image viewer. However, JPEG XL support is included only in the Flathub version.

You can install Flatpak here.