The badge image is vendored rather than hotlinked from snapcraft.io. The CSP
is img-src 'self' data: and would block it anyway, but the reason to leave the
CSP alone is the page's own claim: fetching a badge from someone else's server
hands them the address of every visitor to a page that says no servers are
involved.
The README badge stays dynamic — it reports the published version, and GitHub
proxies images, so no reader is exposed by it.
