Ubuntu Fix: Snap Sandbox Conflict
The "Silent Fail" Root Cause
On modern Ubuntu (22.04+), /usr/bin/chromium-browser is no longer a native binary; it's a wrapper for a Snap package. Snap apps run in a strictly confined environment that prevents OpenClaw (a non-Snap process) from creating or releasing the SingletonLock inside the browser's data directory.
If your logs show a 15-second timeout followed by Permission denied (13) on SingletonLock, your system is blocking OpenClaw from "handshaking" with the browser.
Next Step
Fix now, then reduce repeat incidents
If this issue keeps coming back, validate your setup in Doctor first, then harden your config.
Symptoms
failed to create ~/.openclaw/browser/user-data/SingletonLock: Permission denied
Recommended: Switch to Google Chrome (Native)
The most reliable way to bypass Snap confinement is to use the official Google Chrome .deb package, which does not use the Snap sandbox.
wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb\nsudo apt install ./google-chrome-stable_current_amd64.deb
After installation, update your openclaw.json to point to /usr/bin/google-chrome if it isn't auto-detected.
Alternative: Use the Official PPA for Chromium
If you must use Chromium, you can install the "un-snapped" version from the Linux Mint or System76 PPAs.
sudo add-apt-repository ppa:xtradeb/apps\nsudo apt update\nsudo apt install chromium
Technical Bypass: Change Data Dir
You can try moving the browser user data directory to a path that Snap is allowed to access (like your $HOME directory directly, rather than a hidden subfolder).
// In openclaw.json
"browser": {
"config": {
"userDataDir": "/home/youruser/openclaw-browser-data"
}
}Verification
Run openclaw gateway restart and attempt to launch the browser tool. If the SingletonLock error disappears, the sandbox conflict is resolved.
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