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 ## [Unreleased]
 
+## [v0.51.623] — 2026-06-24 — Release WD (iOS portrait: opening a conversation lands at the bottom)
+
+### Fixed
+
+- **On iOS Safari in portrait, opening or switching a conversation no longer jumps to the top of the transcript.** iOS resolves its dynamic toolbar height after first paint; when the toolbar collapsed, the message scroller grew and fired a scroll event with a decreased `scrollTop` that the WebUI misread as the user scrolling up — so it unpinned the freshly-opened session and the late re-anchor settle then cancelled itself, stranding the reader at the oldest message (landscape was unaffected because it doesn't resize late). The scroll tracker now distinguishes a container-height increase (toolbar/keyboard reflow) from a real upward scroll, and an open-time settle also re-anchors the bottom after the late portrait viewport change. Desktop and landscape behavior is unchanged. Also addresses the sibling symptom in #4701. (#4702)
+
 ## [v0.51.622] — 2026-06-24 — Release WC (Tasks tab no longer 500s when the cron package is absent)
 
 ### Fixed