Framer loads the snippet from Site Settings. The canvas preview does not.
1. Copy the snippet
In Stellar, open the project for this site and copy the snippet from your domain settings. Leave Anti-Flicker on if you are running visual tests. Direct head install is what makes that work. How anti-flicker works.
2. Paste it on Framer
Open the project and go to Site Settings.
Open General, then Custom Code.
Paste the snippet in the Head field (start of <head>).
Publish.
Open the published URL, either the custom domain or the framer.app address, and confirm the script loads.
Custom code applies after you publish. Checking the canvas is not enough.
3. Confirm it loaded
Open a published page in a private browser window. Editor and draft previews often hide the snippet.
Open developer tools and go to the Network tab.
Reload and look for stellar.js. If that request is there, the install is done.
If it does not load
Confirm you published after pasting. An older publish will not include the snippet.
If both a custom domain and a framer.app URL are live, check the one you will actually test.
Paste it once. A second copy in a page embed will conflict.