Grabbed dndbeyond's source code

```
~/go/bin/sourcemapper -output ddb -jsurl https://media.dndbeyond.com/character-app/static/js/main.90aa78c5.js
```

ddb_main/components/Textarea/Textarea.tsx

@@ -0,0 +1,75 @@
+import clsx from "clsx";
+import {
+  forwardRef,
+  HTMLAttributes,
+  useEffect,
+  useImperativeHandle,
+  useRef,
+  useState,
+} from "react";
+
+import styles from "./styles.module.css";
+
+export interface TextareaProps
+  extends Omit<HTMLAttributes<HTMLDivElement>, "children"> {
+  value?: string;
+  onInputBlur: (textValue: string) => void;
+  onInputKeyUp: () => void;
+}
+
+/**
+ * A component to be used as a text area with auto-resizing capabilities. This
+ * is used in the panes for notes and traits and needs to support text entry as
+ * well as programmatic updates.
+ */
+export const Textarea = forwardRef<HTMLDivElement, TextareaProps>(
+  (
+    { className, value, onInputBlur, onInputKeyUp, placeholder, ...props },
+    forwardedRef
+  ) => {
+    const [currentValue, setCurrentValue] = useState(value);
+
+    const ref = useRef<HTMLDivElement>(null);
+    // Combine the local ref with the forwarded ref
+    useImperativeHandle(forwardedRef, () => ref.current as HTMLDivElement);
+
+    const handleChange = (e) => {
+      const dataSet = e.target.parentNode.dataset;
+      dataSet.value = e.target.value;
+      setCurrentValue(e.target.value);
+    };
+
+    const handleBlur = (e) => onInputBlur(e.target.value);
+    const handleKeyUp = () => onInputKeyUp();
+
+    useEffect(() => {
+      if (ref.current) {
+        const wrapper = ref.current as HTMLDivElement;
+        const textarea = wrapper.children[0] as HTMLTextAreaElement;
+        // Set the data-value attribute to the value
+        wrapper.dataset.value = value;
+        // Set the textarea value to the value
+        textarea.value = value || "";
+        setCurrentValue(value);
+      }
+    }, [value]);
+
+    return (
+      <div
+        className={clsx([styles.textarea, className])}
+        ref={ref}
+        data-value={currentValue}
+        {...props}
+      >
+        <textarea
+          rows={1}
+          placeholder={placeholder}
+          onChange={handleChange}
+          onKeyUp={handleKeyUp}
+          onBlur={handleBlur}
+          value={currentValue}
+        />
+      </div>
+    );
+  }
+);