LibreChat/client
Danny Avila 562bd8ec5f
🐛 fix: Prevent Infinite Render Loop on Code-Execution File Preview (#13922)
* 🐛 fix: Prevent Infinite Render Loop on Code-Execution File Preview

Loading a conversation that contains a large (>1MB) code-execution
office file crashed the whole app with React error #185 ("Maximum
update depth exceeded") on hard refresh.

Root cause (client-only): the terminal-write effect in
useAttachmentPreviewSync writes the resolved preview record back into
messageAttachmentsMap with a fresh object identity on every run, and
`attachment` is in the effect's dependency array. useAttachments
re-derives `attachment` ({...db, ...liveEntry}) with a new identity on
every map write, so once polling resolves (pending -> ready on a loaded
conversation) the effect ping-pongs forever:
setAttachmentsMap -> re-derive -> effect -> setAttachmentsMap.

Only files large/slow enough to defer extraction are persisted at
status: 'pending', which is why small documents never triggered it.

Fix: an idempotency gate that bails before setAttachmentsMap when the
merged attachment already carries the resolved status/text/textFormat/
previewError. The write happens once and then settles.

Tests:
- useAttachmentPreviewSync.loop.spec.tsx wires the real
  useAttachments -> hook feedback to reproduce the loop (verified to
  throw #185 without the gate, settle with it).
- e2e/specs/mock/attachment-preview-loop.spec.ts loads a conversation
  with a pending code-exec attachment whose preview resolves ready and
  asserts the app does not crash.

Closes #13916

* 🔧 feat: Make Office Preview Extraction Cap Configurable (default 2MB)

The inline code-execution preview extraction ceiling was a hardcoded 1MB
constant (MAX_TEXT_EXTRACT_BYTES). Office/text artifacts over that skip
the inline preview and resolve to "Preview unavailable" (download-only).

Make it configurable via FILE_PREVIEW_MAX_EXTRACT_BYTES and raise the
default to 2MB so larger documents get an inline preview out of the box.
The rendered HTML remains independently capped at MAX_TEXT_CACHE_BYTES
(512KB), so image-heavy files over that still fall back to the existing
"preview too large" banner rather than rendering unbounded output.

- resolveMaxTextExtractBytes(env) parses the override, falling back to
  2MB on missing/non-numeric/non-positive values (warns on invalid).
- Documented in .env.example next to the other file-size limits.
- Unit tests cover default, valid override, fractional flooring, and
  invalid fallback.

* 🐛 fix: Guard sub-byte preview cap from flooring to zero

A fractional FILE_PREVIEW_MAX_EXTRACT_BYTES in (0, 1) passed the
positive-number check then floored to 0, making MAX_TEXT_EXTRACT_BYTES
zero and treating every non-empty artifact as oversized. Floor first,
then require the result to be >= 1 byte before accepting it; otherwise
fall back to the 2 MB default. Adds coverage for the sub-byte case.

*  test: Make exported-ceiling assertion env-independent

The "exported ceiling" assertion compared MAX_TEXT_EXTRACT_BYTES to a
literal 2 MB, but that const is initialized from
FILE_PREVIEW_MAX_EXTRACT_BYTES at module load — so the suite would
falsely fail when run with the override set. Assert the export tracks
resolveMaxTextExtractBytes(env) for the current environment instead; the
undefined-case test continues to pin the 2 MB default.
2026-06-23 16:34:43 -04:00
..
public 🎨 chore: Update Agent Tool with new SVG assets (#12065) 2026-03-04 09:28:19 -05:00
scripts
src 🐛 fix: Prevent Infinite Render Loop on Code-Execution File Preview (#13922) 2026-06-23 16:34:43 -04:00
sw 🛟 fix: Auto-Recover from Stale Service Worker Assets After Deploys (#13686) 2026-06-11 11:57:06 -04:00
test 🧑‍🎨 refactor: Prompts/Sidebar styles for improved UI Consistency (#12426) 2026-04-09 00:02:31 -04:00
babel.config.cjs 🧑‍🎨 refactor: Prompts/Sidebar styles for improved UI Consistency (#12426) 2026-04-09 00:02:31 -04:00
check_updates.sh
index.html 🛟 fix: Auto-Recover from Stale Service Worker Assets After Deploys (#13686) 2026-06-11 11:57:06 -04:00
jest.config.cjs v0.8.7-rc1 (#13592) 2026-06-15 13:10:30 -04:00
nginx.conf 🐳 feat: Bundle Admin Panel in Docker Compose Stacks (#13876) 2026-06-22 16:59:08 -04:00
package.json 👐 a11y: Bump @ariakit/react, Improve a11y of Token Usage, Archived Chats, Reduce Table Layout Shifts (#13874) 2026-06-21 12:53:24 -04:00
postcss.config.cjs
tailwind.config.cjs ⌨️ feat: Keyboard Shortcuts (#12425) 2026-06-22 17:02:46 -04:00
tsconfig.json 👷 ci: Type-check the Client Workspace (#13560) 2026-06-06 18:40:31 -04:00
vite.config.ts 🛟 fix: Auto-Recover from Stale Service Worker Assets After Deploys (#13686) 2026-06-11 11:57:06 -04:00