Troubleshooting
Most issues are one of a handful of things. Work down the list.
"The bridge isn't awake on this computer"
The Print Bridge isn't running here. Install it (or launch it if already installed), then click Check again. On Linux you can confirm it's up by opening http://127.0.0.1:9110.
My printer doesn't appear
- Confirm the OS sees it: it should be listed in your system's Printers & Scanners (Windows/macOS) or via CUPS (Linux).
- Re-plug USB or re-check the network printer, then click Check again.
- Make sure you chose Allow on the browser's local-network prompt (see Connect a printer).
The label prints small / shrunk to a page
That's page scaling, not the printer. Print through the app (not the browser dialog) so it goes out at true size — full details in Printing at true size.
The browser never asked to connect to local devices
Click the site-info icon in the address bar and allow local network access, then reload. In Chrome 142+ this is the Local Network Access permission.