I also encountered a problem when trying to install Obsidian on Ubuntu 26. My first installation using Snap failed: Obsidian wouldn’t open and didn’t produce any logs. After tracing system calls in the console (strace obsidian), I concluded that Snap’s Obsidian wasn’t compatible with the Wayland environment (the primary user interface protocol in the new Ubuntu 26). Obsidian from the installation package launched without any issues.