Telegram: empty HTML still reproducible on current main for '>' and '[]()' causing empty-text send failures #25091
Description
Summary
The Telegram empty-text bug is still reproducible on the current upstream/main.
While validating PR #17629, I reproduced formatter outputs that become empty HTML for specific markdown inputs. This still creates a path where Telegram can reject sendMessage with 400: Bad Request: message text is empty (especially in threaded delivery paths).
Repro (latest main)
- Repo:
openclaw/openclaw - Branch/commit:
upstream/main@8ea936cdd - Date: 2026-02-24
Added a focused test on upstream/main and confirmed:
markdownToTelegramHtml('>') === ''markdownToTelegramHtml('[]()') === ''
Why this still matters
If rendered HTML is empty and passed through Telegram send paths, Telegram rejects the message body with:
400: Bad Request: message text is empty
Related history
- Prior stale issue: Telegram threaded replies fail with empty message text #7186
- Prior closed PR: fix(telegram): preserve reply text in threaded mode dispatch #17769
- Current canonical fix PR: fix(telegram): fall back to plain text when HTML formatter produces empty output #17629
Proposed path
Use #17629 as the canonical fix path (it adds formatter safety net + delivery fallback) and re-triage against current main based on the reproducible cases above.