Files were being served with Cache-Control: max-age=18144000 (210 days)
keyed only on the upstream ?v=<sha>. Editing the term list left the
same URL serving stale anonymized bytes — visible to users in regular
tabs but not in incognito. The previous fix-by-incognito recipe in #439
is exactly this.
Switch to ETag-based revalidation that fingerprints both the upstream
sha and the saved anonymization options, with Cache-Control:
no-cache, must-revalidate. Browsers now revalidate on every request and
get a 304 when nothing has changed, or fresh content as soon as terms,
image/link/etc. options are updated.
Fixes#439.
tdurieux