fix: 🐛 google doc paste (#1773)

* fix: 🐛 google doc paste

✅ Closes: #1209

* [autofix.ci] apply automated fixes

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

Author: Saul-Mirone

Diff for: packages/plugins/preset-commonmark/src/mark/strong.ts

@@ -26,9 +26,22 @@ export const strongSchema = $markSchema('strong', (ctx) => ({
     },
   },
   parseDOM: [
-    { tag: 'b' },
+    // This works around a Google Docs misbehavior where
+    // pasted content will be inexplicably wrapped in `<b>`
+    // tags with a font-weight normal.
+    {
+      tag: 'b',
+      getAttrs: (node: HTMLElement) =>
+        node.style.fontWeight != 'normal' && null,
+    },
     { tag: 'strong' },
     { style: 'font-style', getAttrs: (value) => (value === 'bold') as false },
+    { style: 'font-weight=400', clearMark: (m) => m.type.name == 'strong' },
+    {
+      style: 'font-weight',
+      getAttrs: (value: string) =>
+        /^(bold(er)?|[5-9]\d{2,})$/.test(value) && null,
+    },
   ],
   toDOM: (mark) => ['strong', ctx.get(strongAttr.key)(mark)],
   parseMarkdown: {