fix(mdviewer): code block line annotation on first load, disable spellcheck

Fix _annotateCodeBlockLines to work even when morphdom strips
data-source-line from <pre> on first render — falls back to estimating
source line from nearest preceding sibling. Skip already-annotated
blocks to avoid double processing.

Disable spellcheck, autocorrect, autocomplete, and autocapitalize on
all code blocks in the viewer.

Remove debug exports and restore sandbox.

Author: abose

src-mdviewer/src/bridge.js

@@ -9,7 +9,6 @@ import { setLocale } from "./core/i18n.js";
 import { marked } from "marked";
 import * as docCache from "./core/doc-cache.js";
 import { broadcastSelectionStateSync } from "./components/editor.js";
-import { renderAfterHTML } from "./components/viewer.js";
 
 let _syncId = 0;
 let _lastReceivedSyncId = -1;
@@ -572,16 +571,11 @@ function handleSetContent(data) {
         docCache.switchTo(filePath);
     }
 
-    // Run post-render processing (Prism highlighting, code block line annotation)
-    const content = document.getElementById("viewer-content");
-    if (content) {
-        renderAfterHTML(content, parseResult);
-    }
-
     setState({
         currentContent: markdown,
         parseResult: parseResult
     });
+    // file:rendered triggers viewer.js handler which does morphdom + renderAfterHTML
     emit("file:rendered", parseResult);
     _suppressContentChange = false;
 }
@@ -675,13 +669,6 @@ function handleSwitchFile(data) {
         // Cache hit, content unchanged — instant switch
         docCache.switchTo(filePath);
 
-        // Ensure code blocks are highlighted and line-annotated (may be missing on first load)
-        const cachedContent = document.getElementById("viewer-content");
-        if (cachedContent && !cachedContent.querySelector("pre code span[data-source-line]") &&
-            cachedContent.querySelector("pre[data-source-line]")) {
-            renderAfterHTML(cachedContent, existing.parseResult);
-        }
-
         setState({
             currentContent: markdown,
             parseResult: existing.parseResult
@@ -706,12 +693,6 @@ function handleSwitchFile(data) {
         docCache.createEntry(filePath, markdown, parseResult);
         docCache.switchTo(filePath);
 
-        // Run post-render processing on newly created entry
-        const newContent = document.getElementById("viewer-content");
-        if (newContent) {
-            renderAfterHTML(newContent, parseResult);
-        }
-
         // Restore scroll position and edit mode from reload if applicable
         if (_pendingReloadScroll && _pendingReloadScroll.filePath === filePath) {
             const entry = docCache.getEntry(filePath);

src-mdviewer/src/components/viewer.js

@@ -183,6 +183,14 @@ export function highlightCode() {
         Prism.highlightElement(block);
     });
 
+    // Disable spellcheck and autocomplete inside code blocks
+    document.querySelectorAll("#viewer-content pre").forEach((pre) => {
+        pre.spellcheck = false;
+        pre.setAttribute("autocorrect", "off");
+        pre.setAttribute("autocomplete", "off");
+        pre.setAttribute("autocapitalize", "off");
+    });
+
     // After Prism highlighting, add per-line data-source-line spans inside code blocks
     _annotateCodeBlockLines();
 }
@@ -193,12 +201,33 @@ export function highlightCode() {
  * Must run AFTER Prism highlighting since Prism replaces innerHTML.
  */
 function _annotateCodeBlockLines() {
-    const pres = document.querySelectorAll("#viewer-content pre[data-source-line]");
+    // Process all pre elements, not just those with data-source-line
+    // (morphdom may strip the attr on first render)
+    const pres = document.querySelectorAll("#viewer-content pre");
     pres.forEach((pre) => {
         const code = pre.querySelector("code");
         if (!code) return;
-        const preSourceLine = parseInt(pre.getAttribute("data-source-line"), 10);
-        if (isNaN(preSourceLine)) return;
+        // Already annotated?
+        if (code.querySelector("span[data-source-line]")) return;
+
+        let preSourceLine = parseInt(pre.getAttribute("data-source-line"), 10);
+        if (isNaN(preSourceLine)) {
+            // Fallback: find the nearest preceding sibling with data-source-line
+            // and estimate this pre's line from it
+            let prev = pre.previousElementSibling;
+            while (prev && !prev.hasAttribute("data-source-line")) {
+                prev = prev.previousElementSibling;
+            }
+            if (prev) {
+                const prevLine = parseInt(prev.getAttribute("data-source-line"), 10);
+                // Rough estimate: count text lines in the previous element
+                const prevText = prev.textContent || "";
+                const prevLines = (prevText.match(/\n/g) || []).length + 1;
+                preSourceLine = prevLine + prevLines + 1; // +1 for blank line between
+            } else {
+                return; // Can't determine line, skip
+            }
+        }
         // Code content starts after the ``` line
         const codeStartLine = preSourceLine + 1;