Fix raw </pre> handling in response renderer by bsgdigital · Pull Request #1150 · nesquena/hermes-webui

bsgdigital · 2026-04-27T13:04:20Z

Bug Description

Fixes response rendering where raw HTML code blocks could consume following content.

When model output included raw <pre><code>...</code></pre>, later message content could be rendered as if still inside a code box. This was especially visible when multiple code boxes appeared in one response.

Root Cause

renderMd() in static/ui.js performs a safe inline-HTML normalization pass that rewrites <code>...</code> to markdown backticks.

That rewrite was applied globally, including inside raw <pre> blocks coming from model output. For multiline code inside <pre><code>...</code></pre>, this could degrade block structure (introducing stray backticks and malformed code-box boundaries), which then cascaded into subsequent content rendering incorrectly.

Fix

Stash raw <pre>...</pre> blocks before the inline <code> normalization pass, then restore them immediately after.

// Before
s = s.replace(/<code>([^<]*?)<\/code>/gi, (_, t) => '`' + t + '`');

// After
const rawPreStash = [];
s = s.replace(/(<pre\b[^>]*>[\s\S]*?<\/pre>)/gi, m => {
  rawPreStash.push(m);
  return `\x00R${rawPreStash.length - 1}\x00`;
});
s = s.replace(/<code>([^<]*?)<\/code>/gi, (_, t) => '`' + t + '`');
s = s.replace(/\x00R(\d+)\x00/g, (_, i) => rawPreStash[+i]);

This is a minimal, targeted change: only raw <pre> regions are protected from the inline <code> rewrite; the rest of the markdown pipeline remains unchanged.

Files Changed

static/ui.js — protect raw <pre> blocks during inline HTML normalization
tests/test_renderer_js_behaviour.py — add regression test for multiple multiline raw <pre><code> blocks

How to Verify

Send output that contains multiple raw HTML code blocks, e.g.:

"Return two raw HTML code blocks using <pre><code>...</code></pre>, each multiline, with plain text between and after them."

Before fix: code-box boundaries could degrade and later content could appear inside a code box.
After fix: each code block stays balanced and plain text between/after blocks renders normally.

Test Plan

Added regression test in tests/test_renderer_js_behaviour.py (TestRawPreCodePreservation)
Ran direct Node renderMd smoke verification for multiline raw <pre><code> blocks
Confirmed touched files have no lints
Full local pytest run

Risk Assessment

Low — change scope is limited to stashing/restoring raw <pre> segments around one inline rewrite pass. No CSS/layout changes and no behavior changes for fenced markdown code blocks.

nesquena-hermes · 2026-04-27T13:47:28Z

Thanks for this PR! The stash-and-restore pattern for protecting raw <pre> blocks is the correct approach for this class of rendering bug.

The fix is well-targeted:

Stashing <pre>...</pre> blocks before the inline <code> normalization pass, then restoring them after, is minimal and precise
The null-byte sentinel (\x00R{i}\x00) is a good choice — won't appear in normal content
The regression test in test_renderer_js_behaviour.py covering multiple multiline <pre><code> blocks is exactly what's needed to lock this in

One note on scope: The PR also includes commits touching api/updates.py and server.py related to auto-reapplying local patches after upstream sync (feat(update): auto-reapply local patches after upstream sync). That's a significant and separate feature bundled with this renderer fix. The maintainer may want to consider separating these concerns — the renderer fix is a clean low-risk change, while the update/patch management changes are higher-risk and warrant independent review.

Files changed:

static/ui.js (+6/0) — the core renderer fix
tests/test_renderer_js_behaviour.py (+27/0) — regression test
api/updates.py (+124/-27) — local patches update flow (unrelated to renderer fix)
server.py (+76/0) — startup branch enforcement (unrelated to renderer fix)
tests/test_local_patches_update_flow.py (+77/0) — tests for the update flow

The renderer fix itself looks correct and low-risk. The bundled update management changes will need separate careful review.

nesquena-hermes · 2026-04-27T19:21:39Z

🔴 Hold: Please split into two PRs

This PR is being placed on hold because it bundles two unrelated changes that each deserve their own review track.

Change 1 — `static/ui.js` `renderMd()` pre-block fix ✅

The stash/restore logic for raw <pre> blocks is clean, self-contained, and valuable. We want this. It's easy to review in isolation and has no side-effects on other subsystems.

Change 2 — `server.py` + `api/updates.py` local-patches branch flow 🔍

The _ensure_active_branch() startup logic that auto-switches the repo to a local-patches branch is a complex behavioral change: it alters how the server initialises, affects update flows, and could have meaningful impact on users' git state. This warrants its own focused review, dedicated testing notes, and a separate discussion thread.

Requested action

Please split this into two PRs:

PR A — only static/ui.js renderMd pre-block stash/restore fix
PR B — server.py + api/updates.py local-patches branch flow (with context on motivation, edge cases handled, and rollback behaviour)

Once split, PR A can move quickly. PR B can get the deeper review it needs without blocking the UI fix.

Thanks for the work here — both changes look like they're solving real problems, just easier to ship safely when reviewed separately.

/hold

Stash raw pre blocks before inline code-tag normalization so multiline code content is not rewritten into stray backticks that can corrupt subsequent code box rendering. Add a JS-renderer behavior test that guards balanced pre/code output across multiple raw code blocks. Made-with: Cursor

Rename the raw pre stash variable so static substring checks for _pre_stash continue to target the intended code-block stash section. Made-with: Cursor

bsgdigital · 2026-04-27T19:41:47Z

@nesquena-hermes apologies, fixed now

nesquena-hermes · 2026-04-27T22:08:19Z

Integrated via #1172. Thank you @bsgdigital!

@bsgdigital

…, .env (#1179) Merged as v0.50.228. 2644 tests passing. Browser QA 21/21 (desktop 1440×900 + mobile iPhone 14). All 5 fix invariants verified live in browser. **Fix verifications:** - #1172 (`renderMd` pre-stash): `rawPreStash` present in function, `<pre>` blocks pass through without content rewrite ✅ - #1174 (model race guard): `syncTopbar()` contains `liveStillPending` guard ✅ - #1175 (tool card): `.tool-card-result pre` max-height=360px, `.tool-card.open .tool-card-detail` overflow=auto, cap=600px ✅ - #1176 (empty session guard): double-click New Conversation on empty session → stays on same session, composer focused ✅ - #1178 (`.env` atomic write): `tempfile.mkstemp + os.replace` in `providers.py`, 9/9 env tests pass ✅ Thanks @bsgdigital (#1150) and @bergeouss (#1178)!

@bsgdigital

…, .env (nesquena#1179) Merged as v0.50.228. 2644 tests passing. Browser QA 21/21 (desktop 1440×900 + mobile iPhone 14). All 5 fix invariants verified live in browser. **Fix verifications:** - nesquena#1172 (`renderMd` pre-stash): `rawPreStash` present in function, `<pre>` blocks pass through without content rewrite ✅ - nesquena#1174 (model race guard): `syncTopbar()` contains `liveStillPending` guard ✅ - nesquena#1175 (tool card): `.tool-card-result pre` max-height=360px, `.tool-card.open .tool-card-detail` overflow=auto, cap=600px ✅ - nesquena#1176 (empty session guard): double-click New Conversation on empty session → stays on same session, composer focused ✅ - nesquena#1178 (`.env` atomic write): `tempfile.mkstemp + os.replace` in `providers.py`, 9/9 env tests pass ✅ Thanks @bsgdigital (nesquena#1150) and @bergeouss (nesquena#1178)!

nesquena-hermes mentioned this pull request Apr 27, 2026

Transcript rendering breaks after large tool outputs + diff/log content, showing stray </pre> and corrupting later layout #1154

Closed

nesquena-hermes added the hold label Apr 27, 2026

bsgdigital added 2 commits April 27, 2026 19:40

fix(tests): avoid pre-stash name collision in renderer

18870cf

Rename the raw pre stash variable so static substring checks for _pre_stash continue to target the intended code-block stash section. Made-with: Cursor

bsgdigital force-pushed the fix/pre-tag-response-parsing branch from f0359fc to 18870cf Compare April 27, 2026 19:40

nesquena-hermes mentioned this pull request Apr 27, 2026

fix: batch triage — 12 contributor PRs (v0.50.227) #1168

Merged

nesquena-hermes removed the hold label Apr 27, 2026

nesquena-hermes mentioned this pull request Apr 27, 2026

fix(renderer): preserve raw <pre> blocks during markdown rewrites (v0.50.228) #1172

Closed

nesquena-hermes closed this Apr 27, 2026

nesquena-hermes mentioned this pull request Apr 27, 2026

fix: batch release v0.50.228 — renderer, model race, tool card, empty session, .env #1179

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Fix raw </pre> handling in response renderer#1150

Fix raw </pre> handling in response renderer#1150
bsgdigital wants to merge 2 commits intonesquena:masterfrom
bsgdigital:fix/pre-tag-response-parsing

bsgdigital commented Apr 27, 2026 •

edited

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nesquena-hermes commented Apr 27, 2026

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bsgdigital commented Apr 27, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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Bug Description

Root Cause

Fix

Files Changed

How to Verify

Test Plan

Risk Assessment

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nesquena-hermes commented Apr 27, 2026

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nesquena-hermes commented Apr 27, 2026

🔴 Hold: Please split into two PRs

Change 1 — static/ui.js renderMd() pre-block fix ✅

Change 2 — server.py + api/updates.py local-patches branch flow 🔍

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bsgdigital commented Apr 27, 2026

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bsgdigital commented Apr 27, 2026 •

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Change 1 — `static/ui.js` `renderMd()` pre-block fix ✅

Change 2 — `server.py` + `api/updates.py` local-patches branch flow 🔍