- Skip and latch a bounded Shell window once the browser is at xterm's
scrollback cap (scrollback + rows): a 1 MiB window of short lines can carry
more rows than the browser can ever hold, so it replayed and re-captured on
every scroll-to-top with no 60 s back-off.
- Label a replayed bounded window 'tail' even when the capture was byte-capped,
so the banner keeps offering Load full history instead of calling the rest
unrecoverable.
- Pin GET /terminal?full=1&tail=<n> in the route tests: full-history source,
truncationReason 'tail', and the closing relative cursor move survive the cut.
- Log the bounded skip via _logScrollRouting('repull-skipped-bounded').
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
A window cut at the tail size can be smaller than the browser's buffer
while tmux still holds more. The downgrade guard reads that as "tmux has
nothing more to give", which is true of an unbounded capture only, so a
bounded window reaching it marked the session exhausted and removed Load
full history from the banner.
The bounded skip now runs first, so such a window never reaches the
exhausted path, and it no longer writes banner state: relabelling it from
the bounded payload would call a terminal holding all of a Load full
history pull "the most recent 1 MiB".
A skipped window that came back truncated cannot reach anything older
than the browser shows, and every ask costs the server a synchronous
capture-pane of the whole history (tail is applied after the capture), so
it puts the session on the 60 s cooldown. An untruncated one keeps 4 s.
_replayWouldShrinkBuffer takes optional pre-estimated rows so a megabyte
capture is not scanned twice. CLAUDE.md's Full-scrollback replay entry no
longer says Shell never pulls on ordinary scroll.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Closes#259, closes#258. Both bottom out in the same gap: nothing tracked
whether the user was following live output or reading history.
#259 — the keyboard path forced the terminal to the bottom unconditionally
(onKeyboardShow/onKeyboardHide passed scrollToBottom:true, applied with no
check), so opening the keyboard while scrolled up yanked the user down. The
settle cycle now captures intent on its FIRST event, before any fit() has
reflowed the buffer, and returns to that anchor when the user was reading.
A later capture would read an already-moved viewportY, which is why the
capture point matters. The param is renamed restoreScroll to match.
Separately, flushPendingWrites gated viewport preservation on
_hasRecentUserScrollUp(), a 1500ms decay window, so a user who scrolled up and
then actually READ for longer lost protection mid-read. Being scrolled up IS
the intent however long ago it was expressed, so it now keys off position.
The recency window stays as a race guard on the sticky scroll-to-bottom.
The full-history repull already held the user's place and is unchanged.
#258 — truncation was reported by a grey line written INTO the terminal
("earlier output truncated"), which scrolls away with the output it describes,
cannot be acted on, and said the same thing whether the rest was one click away
or gone forever. The server set one `truncated` boolean at two sites meaning
opposite things, and the client discarded fullSize and source entirely.
The route now reports truncationReason ('tail' = intentional partial replay,
the rest is retained; 'capped' = the byte ceiling dropped it) plus
retainedBytes, and 'capped' is not downgraded by a later tail cut. The client
renders a dismissible banner outside terminal output with three honest states:
recoverable (offers Load full history), at-ceiling, and exhausted. The Load
button forces past the scroll cooldown but NOT past _replayWouldShrinkBuffer,
which still refuses a downgrade for repaint-mode panes.
The banner is an overlay, not a flex child: FitAddon derives rows/cols from the
terminal parent's computed height, so occupying real layout space would SIGWINCH
the CLI on every truncation-state change.
Verified in a real browser on the 7 skins: banner text and button clear 4.5:1
contrast on all of them, and terminal height is byte-identical with the banner
shown. The first cut used --bg-elevated and --accent-muted, which do not exist,
so light skins rendered a hardcoded dark bar under dark text; it now uses only
tokens every skin redefines.
test/terminal-scroll-intent.test.ts lives outside test/mobile/ deliberately —
that suite is excluded from test:ci, so a guard placed there is invisible to CI.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The 1.12.0 retest on #205 reported it still broken in two shapes: a wheel that
did nothing at all on Firefox/macOS (while Fn+Up paged back through intact
text), and iPhone history that went back a little, repeated blocks and got
worse the further up it went. Both come from a Claude pane's LOCAL buffer being
hollow: tmux keeps no history for a repaint-mode pane (history_size 0), so
xterm holds only replayed repaint frames.
1. The scroll-to-top full=1 re-pull now refuses a DOWNGRADE. It resets the
terminal and rewrites it from the capture, which is a win when tmux holds
more than the browser, but for a repaint-mode pane that capture is roughly
ONE frame and the rewrite deleted history mid-scroll. Measured A/B on a live
pane, same gesture: guard off collapses 341 rows to 42, guard on preserves
all 341. _replayWouldShrinkBuffer() estimates the capture's rendered rows
(escapes stripped, capture-pane -J re-wrapping accounted for) and skips the
rewrite when it is more than one screen short; a refused session's cooldown
goes from 4s to 60s so a hollow pane stops re-fetching megabytes.
2. A false forwarding gate on a Claude session no longer means a dead gesture.
Under a triple guard (claude mode, gate false, baseY 0), wheel and touch
travel becomes coalesced PageUp/PageDown through the same 40ms queue as the
SGR reports, at half a screen of travel per page key. Shift is excluded: it
keeps meaning "local scrollback".
3. getClaudeCliVersion() no longer caches FAILURE. It stored null on any
exception and guarded on !== undefined, so one timed-out or PATH-starved
probe at the first Claude session start disabled wheel-forwarding for every
Claude session until the server restarted, which fits a report of breakage on
phone, tablet and laptop at once. Success is still cached for the process
lifetime; failures retry with a 1/2/4 up to 15min backoff, and the policy is
a pure function so the semantics are testable without spawning claude.
4. The terminalWheelLocalScrollback footgun is handled by pairing rather than
scoping: the setting keeps meaning exactly what it says, and fix 2 catches
the case where "local" is empty. The App Settings tooltip now says to leave
it off for Claude/Codex sessions.
5. _logScrollRouting() prints one line per session per distinct decision:
forward-sgr / page-keys / local-scrollback / repull-refused-downgrade, with
mode, cliVersion, the opt-out state, mouse tracking and local scrollback
depth. #205 ran two rounds of remote guesswork over questions that line
answers directly.
Verified end to end against a real isolated instance (own data dir and tmux
socket) with real wheel events: forwarding still sends SGR reports, the opt-out
now sends real PageUp/PageDown where the wheel was dead, a tab-switch collapse
(401 rows to 44) is still fully recovered by the re-pull (back to 401), and a
seeded 341-row Claude buffer survives the same gesture that destroys it with the
guard disabled.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Codeman maintainer