Showing an image's preview when its variant had already been made tied the cached message to state
that changes without touching it: a variant made after the message was cached would never show. It also
cost a query per embedded image, since Action Text loads the embeds without their variant records.
Nothing in the app makes those variants, so the partial no longer looks at them.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Bj8KnxpTf9sj2Ysa8aLAVa
Files are posted as a message's own attachment, and the composer puts none in the rich text: it permits
only mentions and link embeds. The server still keeps any attachment whose signed id resolves, a blob
included, and Action Text's blob partial links to a representation URL that makes the preview on the
first request, without the limits the POST has, and on every request while it fails.
The app's own partial shows an image's preview only if it was already made, and otherwise the file's
name and size, as it does for a file that isn't an image. The cached presentation's version goes up,
since Action Text renders the partial by name and the template digest doesn't see it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Bj8KnxpTf9sj2Ysa8aLAVa
The editor keeps an attachment's content as it finds it, so a hand-written
embed with a url but no href reached the editor with its markup unvalidated,
and a mention saved under Trix's editor carried the generic octet-stream
content type the editor doesn't permit and was dropped on save. Rebuilding
each attachment from its attachable renders the hardened preview partial
and restores the mention content type.
* Bump thruster 0.1.15 → 0.1.23
* Scrub disallowed attributes on allowed tags in message rendering
SanitizeTags removes disallowed tags from message presentation, but
attributes on the tags it allows passed through untouched. Extend the
content-filter chain with a SanitizeAttributes filter that runs Rails'
safe-list sanitizer over the remaining markup, stripping event-handler
attributes and unsafe URI schemes as defense-in-depth alongside the
existing Content-Security-Policy.
Running it after SanitizeTags with the same allowed-tags list makes the
sanitizer's tag pass a no-op, preserving SanitizeTags' remove-not-unwrap
semantics while scrubbing attributes. The attribute allowlist is the
standard ActionText set (which keeps attachments intact) plus class,
which presentation styling relies on.