The .asc files on your capsule show an "Unsupported Content Type (application/pgp-signature;lang=en-US)" page. This is the correct behavior for any unrecognized MIME types.
I can click on "Save to Downloads" on that page (or ⌘S) and view the .asc file locally just fine, both in Lagrange or in a text editor. Local files use UTF-8 text detection because the MIME type information is unavailable.
You could update your Agate .meta files to define the MIME type, e.g., text/plain for these.
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