An attached `.eml` was sanitized and shown in a locked sandbox iframe,
but its remote images still loaded, with no CSP, whatever the user's
remote-content policy said. The preview now uses the viewer's
`sanitizeEmailBodyForIframe` and the strict iframe CSP unless the policy
is `allow`, and sends no referrer.
Behind a reverse proxy at a sub-path (NEXT_PUBLIC_BASE_PATH, e.g.
/webmail) both WOPI requests used a bare fetch('/api/wopi/...') and
reached the mail server instead of the webmail. The status probe came
back 404, so office editing always looked unavailable there - and since
#1047 the probe runs for every opened message, logging the 404 each
time. Route both through apiFetch like every other API call, and cover
the sub-path mount with a test.
Linus Rath
Linus Rath
dealerweb