fix(mdviewer): global edit mode across file switches and underline shortcut tooltip

Edit mode is now preserved globally when switching files instead of
per-document. Added ({mod}+U) shortcut to underline tooltip string.

Author: abose

src-mdviewer/src/bridge.js

@@ -309,19 +309,17 @@ function handleSwitchFile(data) {
 
     _suppressContentChange = true;
 
+    // Edit mode is global for the md editor frame — preserve it across file switches
+    const wasEditMode = getState().editMode;
+
     // Save state for outgoing document
     const outgoingPath = docCache.getActiveFilePath();
     if (outgoingPath) {
         docCache.saveActiveScrollPos();
-        // Save edit mode state in cache entry
-        const outEntry = docCache.getEntry(outgoingPath);
-        if (outEntry) {
-            outEntry._editMode = getState().editMode;
-        }
     }
 
-    // Exit edit mode before switching DOM if currently editing
-    if (getState().editMode) {
+    // Exit edit mode before switching DOM to detach handlers from outgoing element
+    if (wasEditMode) {
         emit("doc:beforeSwitch", { fromPath: outgoingPath, toPath: filePath });
         setState({ editMode: false });
     }
@@ -337,11 +335,6 @@ function handleSwitchFile(data) {
             parseResult: existing.parseResult
         });
 
-        // Restore edit mode for this document
-        if (existing._editMode) {
-            setState({ editMode: true });
-        }
-
         emit("file:switched", { filePath });
     } else if (existing) {
         // Cache hit, content changed — re-render in place
@@ -354,11 +347,6 @@ function handleSwitchFile(data) {
             parseResult: parseResult
         });
 
-        // Restore edit mode for this document
-        if (existing._editMode) {
-            setState({ editMode: true });
-        }
-
         emit("file:rendered", parseResult);
     } else {
         // Cache miss — create new entry
@@ -371,9 +359,7 @@ function handleSwitchFile(data) {
             const entry = docCache.getEntry(filePath);
             if (entry) {
                 entry._scrollSourceLine = _pendingReloadScroll.scrollSourceLine;
-                entry._editMode = _pendingReloadScroll.editMode;
             }
-            const restoreEditMode = _pendingReloadScroll.editMode;
             _pendingReloadScroll = null;
 
             setState({
@@ -394,10 +380,6 @@ function handleSwitchFile(data) {
                     }
                 });
             }
-
-            if (restoreEditMode) {
-                setState({ editMode: true });
-            }
         } else {
             setState({
                 currentContent: markdown,
@@ -407,6 +389,11 @@ function handleSwitchFile(data) {
         }
     }
 
+    // Re-enter edit mode on the new DOM if the frame was in edit mode
+    if (wasEditMode) {
+        setState({ editMode: true });
+    }
+
     _suppressContentChange = false;
 }
 
@@ -438,11 +425,11 @@ function handleCloseFile(data) {
  */
 function handleReloadFile(data) {
     const { filePath } = data;
-    if (!filePath) return;
+    if (!filePath) {
+        return;
+    }
 
     const entry = docCache.getEntry(filePath);
-    const savedScrollPos = entry ? entry.scrollPos : 0;
-    const wasEditMode = entry ? entry._editMode : false;
 
     // If this is the active file, save current scroll
     if (docCache.getActiveFilePath() === filePath) {
@@ -454,7 +441,7 @@ function handleReloadFile(data) {
                 setState({ editMode: false });
             }
             docCache.removeEntry(filePath);
-            _pendingReloadScroll = { filePath, scrollSourceLine, editMode: wasEditMode };
+            _pendingReloadScroll = { filePath, scrollSourceLine };
         }
     } else {
         docCache.removeEntry(filePath);

src-mdviewer/src/locales/en.json

@@ -58,7 +58,7 @@
     "bold": "Bold ({mod}+B)",
     "italic": "Italic ({mod}+I)",
     "strikethrough": "Strikethrough ({mod}+Shift+X)",
-    "underline": "Underline",
+    "underline": "Underline ({mod}+U)",
     "code": "Inline code ({mod}+E)",
     "link": "Link ({mod}+K)",
     "bullet_list": "Bullet list",