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 ## [Unreleased]
 
+## [v0.51.121] — 2026-05-24 — Release CS (stage-batch3 — 4-PR low-risk batch — state.db merge / display counts / compression marker / Windows launcher)
+
+### Fixed
+
+- **PR #2788** by @Carry00 — Prevent `state.db` messages being silently dropped during sidecar merge. Two related bugs were combining to discard historical messages: (1) `get_state_db_session_messages()` was selecting `role, content, timestamp` but NOT `id`, so every row was assigned a `("legacy", ...)` merge key instead of `("message_id", ...)`; (2) when a WebUI-origin session was continued via another Hermes surface (Gateway, CLI), the reader was always hitting the *active* profile's `state.db` rather than the session's own profile. Symptom: a 189-message session showed only 50 in the WebUI. Fix: include `id` in the SELECT when the column exists, and accept an optional `profile=` arg so cross-profile reads use the right database. Both callers in `api/routes.py handle_get` now thread `profile=getattr(s, 'profile', None)` through.
+
+- **PR #2797** by @ai-ag2026 — Align messaging session display counts with deduped display messages. The `message_count` returned by `/api/session` is the display coordinate space used for pagination and the header badge. Messaging-thread `state.db` metadata can carry raw duplicate transport rows (blank assistant separators between Discord/Slack thread turns) that `_merged_session_messages_for_display()` intentionally dedupes for rendering. The advertised count was the raw row count, so the frontend expected phantom messages after dedupe — `len(display_msgs) < message_count` triggered "load older" UI states that immediately returned nothing. Fix: `raw["message_count"] = _merged_message_count` for messaging sessions, computed from the same merge that produced the displayed messages. Adds `tests/test_gateway_sync.py::test_messaging_session_message_count_matches_deduped_display_messages` covering the regression.
+
+- **PR #2803** by @simjak — Compression-summary cards no longer use ordinary tool output that merely mentions context compression. The streaming auto-compression path was using a local broad substring matcher that fired on any message containing the strings "context compaction" / "context compression" / "context was auto-compressed" / "active task list was preserved across context compression", including skill/tool JSON output and ordinary user discussion about compaction. The strict predicate at `api/compression_anchor._is_context_compression_marker()` was already correctly scoped to synthetic marker prefixes on non-tool messages. Fix: expose the strict predicate as `is_context_compression_marker()` (public name) and route `api/streaming._is_context_compression_marker` through it as a backward-compatible alias. Tool/skill output that mentions compression no longer seeds `compression_anchor_summary` cards.
+
+### Added
+
+- **PR #2783** by @Koraji95-coder — Native Windows launcher and community-guide README link (squashed from 3 commits). `start.ps1` is a PowerShell equivalent of `start.sh` that bypasses `bootstrap.py`'s `ensure_supported_platform()` refusal and invokes `server.py` directly on native Windows. It mirrors `start.sh`'s discovery (load optional `.env` with the same readonly-var filter for `UID`/`GID`/`EUID`/`EGID`/`PPID`, find Python via `HERMES_WEBUI_PYTHON` env → `python3` → `python` → `py`, validate `HERMES_WEBUI_AGENT_DIR` on disk before use, prefer the agent's `venv\Scripts\python.exe`, set `HERMES_WEBUI_HOST` / `HERMES_WEBUI_PORT` / `HERMES_WEBUI_STATE_DIR` / `HERMES_HOME` defaults). The README adds a community-maintained native Windows setup section pointing to @markwang2658's `hermes-windows-native-guide` and `hermes-windows-native` repos with the documented memory delta (~330 MB native vs ~1080 MB WSL2+Docker). Closes both halves of #1952. Assumes Python + agent venv are already set up — first-time setup still needs WSL2 once to create the venv (`bootstrap.py` still refuses on native Windows).
+
 ## [v0.51.120] — 2026-05-24 — Release CR (stage-batch2 — 3-PR low-risk batch — Bedrock provider / update check past-tag / CORS preflight)
 
 ### Added