fix: issue with fill tool (#469)

packages/browseros-agent/apps/server/src/browser/browser.ts

@@ -798,25 +798,43 @@ export class Browser {
 
     await elements.scrollIntoView(session, element)
 
+    // Always click to guarantee real keyboard focus.
+    // DOM.focus() is unreliable for shadow DOM, iframes, and custom components.
     let coords: { x: number; y: number } | undefined
     try {
-      await elements.focusElement(session, element)
-      try {
-        coords = await elements.getElementCenter(session, element)
-      } catch {
-        // coordinates are best-effort
-      }
+      const { x, y } = await elements.getElementCenter(session, element)
+      await mouse.dispatchClick(session, x, y, 'left', 1, 0)
+      coords = { x, y }
     } catch {
+      // Fallback to DOM.focus() if we can't get coordinates
       try {
-        const { x, y } = await elements.getElementCenter(session, element)
-        await mouse.dispatchClick(session, x, y, 'left', 1, 0)
-        coords = { x, y }
+        await elements.focusElement(session, element)
       } catch {
-        logger.warn('Could not focus element via click either')
+        logger.warn('Could not focus element via click or DOM.focus()')
+      }
+    }
+
+    if (clear) {
+      // Primary: keyboard select-all + backspace
+      await keyboard.clearField(session)
+
+      // Fallback: if field still has content, triple-click to select all
+      // then typeText will overwrite the selection
+      if (coords) {
+        const value = await elements.getInputValue(session, element)
+        if (value) {
+          await mouse.dispatchClick(
+            session,
+            coords.x,
+            coords.y,
+            'left',
+            3,
+            0,
+          )
+        }
       }
     }
 
-    if (clear) await keyboard.clearField(session)
     await keyboard.typeText(session, text)
     return coords
   }

packages/browseros-agent/apps/server/src/browser/elements.ts

@@ -94,6 +94,23 @@ export async function resolveObjectId(
   return objectId
 }
 
+/** Read the current value/textContent of an input, textarea, or contenteditable element. */
+export async function getInputValue(
+  session: ProtocolApi,
+  backendNodeId: number,
+): Promise<string> {
+  try {
+    const value = await callOnElement(
+      session,
+      backendNodeId,
+      'function(){return this.value??this.textContent??""}',
+    )
+    return (value as string) ?? ''
+  } catch {
+    return ''
+  }
+}
+
 export async function callOnElement(
   session: ProtocolApi,
   backendNodeId: number,

packages/browseros-agent/apps/server/src/browser/keyboard.ts

@@ -1,5 +1,9 @@
+import { platform } from 'node:os'
 import type { ProtocolApi } from '@browseros/cdp-protocol/protocol-api'
 
+// Meta (Cmd) on macOS, Control on everything else
+const PLATFORM_MODIFIER = platform() === 'darwin' ? 4 : 2
+
 type KeyInfo = { code: string; keyCode: number | undefined }
 
 const KEY_MAP: Record<string, KeyInfo> = {
@@ -180,31 +184,33 @@ export async function typeText(
 }
 
 export async function clearField(session: ProtocolApi): Promise<void> {
+  // Select all: Cmd+A on macOS, Ctrl+A on others
   await session.Input.dispatchKeyEvent({
     type: 'keyDown',
     key: 'a',
     code: 'KeyA',
-    modifiers: 2,
+    modifiers: PLATFORM_MODIFIER,
     windowsVirtualKeyCode: 65,
   })
   await session.Input.dispatchKeyEvent({
     type: 'keyUp',
     key: 'a',
     code: 'KeyA',
-    modifiers: 2,
+    modifiers: PLATFORM_MODIFIER,
     windowsVirtualKeyCode: 65,
   })
+  // Backspace to delete selection (more reliable cross-platform than Delete)
   await session.Input.dispatchKeyEvent({
     type: 'keyDown',
-    key: 'Delete',
-    code: 'Delete',
-    windowsVirtualKeyCode: 46,
+    key: 'Backspace',
+    code: 'Backspace',
+    windowsVirtualKeyCode: 8,
   })
   await session.Input.dispatchKeyEvent({
     type: 'keyUp',
-    key: 'Delete',
-    code: 'Delete',
-    windowsVirtualKeyCode: 46,
+    key: 'Backspace',
+    code: 'Backspace',
+    windowsVirtualKeyCode: 8,
   })
 }