When transcript virtualization is disabled (the #4325 opt-out,
_virtualizeTranscript===false), renderMessages() renders every row with no
windowing and never runs the virtualized measure pass
(_updateMessageVirtualMeasurements early-returns when !virtualized). Under
@media (pointer: coarse), .msg-row[data-role="user"] carries
content-visibility: auto; contain-intrinsic-size: auto 96px. Every rebuild does
inner.innerHTML='' then recreates rows as fresh elements, so a fresh off-screen
tall user row (a long paste measuring thousands of px) reserves only the flat
estimate instead of its real height. scrollHeight shrinks by (realHeight -
estimate), the browser force-clamps scrollTop, and the viewport jumps backward
(a browser clamp, JS=none, so scrollTop-write compensation cannot catch it).
#5638 fixed this for the virtualized wipe-and-rebuild path but left the
non-virtualized full-rebuild path uncovered.
Fix, three coordinated parts:
- _estimateUserRowIntrinsicHeight weights CJK / full-width characters as ~2
columns (they wrap at ~24 chars/line, not 48), so a CJK paste reserves close
to its real height even before it is ever measured.
- _applyUserRowIntrinsicHeight reserves max(remembered, estimate): a remembered
height can be a partial paint (a row taller than the viewport only paints its
intersecting slice under content-visibility:auto), so the estimate floors it.
- _rememberRenderedUserRowIntrinsicHeights, called pre-wipe inside
renderMessages, reads the still-laid-out rows' real heights and persists them
keyed by session-relative index, only for rows within the viewport (a fully
off-screen never-painted row reports its collapsed reserve and must not poison
the map), floored at the estimate.
Desktop rests at content-visibility:visible so intrinsic-size is inert there;
verified no behavior change with pointer:fine.
Adds tests/test_issue5744_nonvirtual_userrow_collapse_jumpback.py (7
mutation-checked node-harness tests). Existing #5637/#5638 suites and the
render/virtualization suites pass.
When the anchor row is gone and a virtual top-spacer is present but the snapshot
carries no captured topPadBefore (null), Number(null) is 0, so the topPad-delta
branch would add the ENTIRE current spacer height to scrollTop and fling the reader
far from their content. Guard on an actual (non-null) captured topPadBefore; else
keep the raw fallback target. Mutation-checked (drop the null guard -> the reader is
flung 1300px and the test fails).
Round-2 gate-cert proved the round-1 'snapshot.top + delta' + nearest-to-current
arbiter is mathematically unwinnable: a row's rect offset is scroll-relative
(rect.top - containerRect.top = rowContentPos - scrollTop), so a staged absolute
target only equals the true content-hold when scrollTop == snapshot.top — and in
that exact case the arbiter measures |raw - cur| = 0 and picks raw, writing the
stale value (the reported up-jump, unfixed).
Rework to the app's own realign idiom (mirrors _restoreMessageViewportAnchor and
_compensateScrollForMeasurementDelta): when a measurable anchor row exists, write
el.scrollTop += (currentOffset - capturedOffset) from the LIVE scrollTop — a no-op
when already aligned, a heal when not, no arbiter. Restore the per-tier lookup
guard (key -> sessionIdx, never the rawIdx degradation that maps to a different
message after a virtualization re-window). Genuinely-gone anchor: mirror the
topPad-delta idiom the snapshot already carries (topPadBefore), else keep raw.
Gate-cert tests now use scroll-dependent rect mocks (rect.top = rowContentPos -
scrollTop) so certified hold numbers are physically realizable; mutation-checked
(revert to raw -> the hold tests fail; drop topPad-delta -> that test fails).
_steerClearCurrentOwnerDeadRun cleared busy/activeStreamId/inflight but left
the status line, elapsed timer, and optimistic streaming badge lingering after
a recovered dead run. Add the rest of the app's stale-busy cleanup idiom
(setStatus/setComposerStatus/_clearActivityElapsedTimer/clearOptimisticSessionStreaming),
still bypassing setBusy(false) so its queue-drain can't clobber the restored draft.
vv.scale != 1 means the visual-viewport shrinkage reflects zoom, not the
keyboard; on Chromium 'force enable zoom' that produced a large spurious inset
that jittered on pan. Bail out of the inset when |vv.scale-1|>0.05. + test.
On touch-primary devices (iPad Safari) the on-screen keyboard shrinks the
visual viewport but not the layout viewport, so the bottom-pinned composer
sits behind the keyboard. Compute a --keyboard-bottom-inset from visualViewport
and pad the composer up by it; clear it when the keyboard closes / on
non-touch / no-visualViewport. Reuses the existing visualViewport + pageshow
hooks; no-op on desktop/fine-pointer.
Co-authored-by: nesquena-hermes <nesquena-hermes@users.noreply.github.com>
Strict providers (DeepSeek v4, newer OpenAI) reject an assistant message
carrying tool_calls: [] with HTTP 400. _sanitize_messages_for_api already
strips orphaned tool results, but not an assistant message that literally
stores an empty tool_calls list.
Drop the empty key on ALL THREE sanitized-dict sites that must agree:
_sanitize_messages_for_api, _api_safe_message_positions, and the
_safe_projection inside _restore_reasoning_metadata (so a tool_calls: [] row
projects identically on both sides of the metadata-carry-forward alignment and
doesn't lose its reasoning/id/timestamp every turn — Fable gate follow-up,
folded in).
Added mutation-checked regression tests: empty tool_calls dropped + populated
chain preserved (both sanitizer paths), and metadata carry-forward survives a
tool_calls: [] row.
Co-authored-by: nesquena-hermes <nesquena-hermes@users.noreply.github.com>
test_tls_startup_failure_fallback_to_http read only the first 2000 bytes of
server stdout to assert 'TLS setup failed'. When the test interpreter lacks
optional deps (requests/websockets), startup emits a burst of plugin/tool
import warnings + the startup-config banner BEFORE the TLS line, pushing the
marker past the 2000-byte window -> spurious failure. Drain all
currently-available stdout (5s deadline, short-circuit on the marker) instead
of a single fixed-size read. Verified failing->passing in a fresh venv without
the optional deps. Test-only; distinct from the agent-package-isolation flake
cause already fixed in the same test.
Frontend fix for the model-picker provider-contamination vector of #5567 (the
backend HERMES_HOME vector shipped in #5577). Credit @b3nw for the root-cause trace.
_modelStateForSelect(sel, modelId) resolved the provider from sel.selectedOptions[0]
(the dropdown's CURRENTLY-selected option) instead of the option whose value matches
modelId. During a profile/tab switch or a model-list rebuild the dropdown transiently
still holds the PREVIOUS profile's default option (e.g. an ollama model), so the wrong
provider was stamped onto a model it doesn't own, persisted into the session's
model_provider, and (since _modelProviderForSend reads the stored value first) re-sent
on every turn -> 'Provider ollama...no API key' for a provider the session never used.
Fix: resolve the provider from the option whose VALUE === modelId; trust the
currently-selected option only when its value matches (preserving the user's exact
pick in the same-value/different-provider collision case). A genuinely-absent model
yields a null provider so the backend re-infers.
This is the WRITE-site fix — it stops all NEW contamination (new-session + send paths
route through _modelStateForSelect). Both Codex and Fable reviewed it SAFE.
Repairing sessions ALREADY poisoned before this shipped is deliberately deferred to a
separate follow-up: a 3-round Codex+Fable gate proved a frontend load-time repair that
reads the shared #modelSelect DOM is a cross-session race surface (it re-manufactured
the reverse-contamination it aimed to fix), and it can't reliably heal live-only-model
sessions anyway. The robust place for that repair is the backend chat-start boundary,
where session + profile identity is unambiguous. Already-poisoned sessions self-heal on
their next healthy send / manual re-pick in the meantime.
Tests: node-behavioral resolver scenarios (tab-switch race, same-value collision,
missing-model null, match-by-value, default->null) + the unrelated-selected-option
case from #5727. Partially addresses #5567 (write-vector); follow-up tracks the
already-poisoned-session repair.
Co-authored-by: b3nw <b3nw@users.noreply.github.com>
