Replying to a reply produced "Re: Re: foo" (and German used the English
"Re:"/"Fwd:" instead of "AW:"/"WG:"). Four code paths built reply/forward
subjects and only one deduplicated - and only for the English prefix, so
cross-locale threads accumulated chains.
New lib/subject-prefix.ts strips any leading run of reply/forward markers
across ~35 tokens from all supported languages (plus Outlook Re[2]: and
Eudora Re*2: counters), then prepends the locale-appropriate prefix. All four
call sites (composer getInitialSubject, the two page.tsx sites, and the three
pro-tab handlers) now use buildReplySubject/buildForwardSubject. German prefix
corrected to AW:/WG:.
The quick-reply box built its body with appendPlainTextSignature, which runs
the identity's HTML signature through htmlToPlainText, and sent a text-only
message (htmlBody was undefined). A formatted signature (e.g. <strong>…) was
therefore flattened to plain text in the sent mail, even though it previewed
correctly in the identity editor. The full composer already builds an HTML
signature block; quick reply did not.
Add an appendHtmlSignature helper (mirrors the composer's send-time block) and,
when the sending identity has an HTML signature, send a matching HTML body from
handleQuickReply so the markup is preserved. Text-only identities keep the
plain-text-only behavior.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
