fix(terminal): dimmed text on a filled background no longer renders invisible - #279
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fix(terminal): dimmed text on a filled background no longer renders invisible#279vakovalskii wants to merge 1 commit into
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…nvisible Claude Code (and other TUIs) draw some rows as *dimmed* text on a filled background — e.g. the grey 'message above' bars. In a codbash pane those bars came out as empty grey strips with no text at all, while the same output stayed legible in iTerm. Cause: xterm's minimumContrastRatio defaults to 1, which disables all contrast adjustment — and the dim path is gated behind it (xterm.js: 'minimumContrastRatio||(0…)' and 'minimumContrastRatio/(s.isDim(…)'). The WebGL renderer applies dim by cutting the foreground alpha, so with no adjustment dim-on-background washes out to invisible. Both the webgl and canvas addons honor the option. Fix: set minimumContrastRatio to 4.5 (WCAG AA). xterm only nudges a foreground when it falls below the ratio, so normal colors are untouched. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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* fix(terminal): dimmed text on a filled background no longer renders invisible Claude Code (and other TUIs) draw some rows as *dimmed* text on a filled background — e.g. the grey 'message above' bars. In a codbash pane those bars came out as empty grey strips with no text at all, while the same output stayed legible in iTerm. Cause: xterm's minimumContrastRatio defaults to 1, which disables all contrast adjustment — and the dim path is gated behind it (xterm.js: 'minimumContrastRatio||(0…)' and 'minimumContrastRatio/(s.isDim(…)'). The WebGL renderer applies dim by cutting the foreground alpha, so with no adjustment dim-on-background washes out to invisible. Both the webgl and canvas addons honor the option. Fix: set minimumContrastRatio to 4.5 (WCAG AA). xterm only nudges a foreground when it falls below the ratio, so normal colors are untouched. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> * feat(terminal): name a terminal pane yourself The pane title bar showed only an auto-label — the running agent, the project folder, or a bare '~' for home. With several panes open in the same folder (or several shells in $HOME) they were indistinguishable. You can now give a pane its own name: click the ✎ in its title bar, or double-click the title. An empty answer clears the name and restores the auto-label. Uses codbashPrompt (window.prompt is a no-op in the Electron shell). The name round-trips: it is captured into the session snapshot and saved layouts, restored at every pane-construction site, and sanitizePane now preserves it (reusing the existing MAX_NAME=120 cap and rejecting control characters, like the other pane fields). Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> * release: 7.17.0 — named terminal panes + readable dimmed text Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
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Симптом
В панели Terminal строки, которые Claude Code рисует приглушённым текстом на залитом фоне (серые полосы «сообщение выше»), выглядели как пустые серые полосы вообще без текста. Тот же самый вывод в iTerm читается нормально — то есть текст не терялся, а не отрисовывался.
Репортил @vakovalskii, воспроизводится повсеместно, а не в каком-то одном месте.
Причина
Найдена в вендоренном xterm.js:
Коррекция контраста целиком закрыта за этой опцией, а её дефолт —
1, то есть выключено. Мы её не выставляли. WebGL-рендерер реализуетdimчерез срез альфы переднего плана, поэтому без коррекции приглушённый текст на залитом фоне схлопывается до неразличимого. iTerm приглушает мягче, отсюда разница.Оба наших аддона опцию учитывают:
addon-webgl.jsиaddon-canvas.jsссылаются на неё и активно работают сdim(21 и 13 упоминаний соответственно).Фикс
Одна строка —
minimumContrastRatio: 4.5(WCAG AA) в опцияхTerminal. xterm правит цвет только когда контраст падает ниже порога, поэтому обычные цвета темы не затрагиваются.Проверка
node --test test/*.test.js→ 253 passed / 0 failed / 2 skippednode bin/cli.js runна этой ветке → вкладка Terminal → запустить агента и прокрутить историю; серые полосы должны показывать текст.Отдельно отмечу: в ходе разбора я сначала ошибочно списал это на служебную обёртку
<local-command-caveat>в транскрипте (она действительно рисуется как пустой серый бокс, но только у!-команд) — сообщение @vakovalskii «такое у меня везде» это опровергло и вывело на настоящую причину.🤖 Generated with Claude Code