diff --git a/atom/browser/api/atom_api_web_contents.cc b/atom/browser/api/atom_api_web_contents.cc
index f59b72bd0c9c..aa9f539bd93a 100644
--- a/atom/browser/api/atom_api_web_contents.cc
+++ b/atom/browser/api/atom_api_web_contents.cc
@@ -895,10 +895,10 @@ void WebContents::DevToolsOpened() {
   managed_web_contents()->CallClientFunction(
       "DevToolsAPI.setInspectedTabId", &tab_id, nullptr, nullptr);
 
-  // Inherit owner window in devtools.
+  // Inherit owner window in devtools when it doesn't have one.
   auto* devtools = managed_web_contents()->GetDevToolsWebContents();
-  if (owner_window() &&
-      !devtools->GetUserData(NativeWindowRelay::UserDataKey()))
+  bool has_window = devtools->GetUserData(NativeWindowRelay::UserDataKey());
+  if (owner_window() && !has_window)
     handle->SetOwnerWindow(devtools, owner_window());
 
   Emit("devtools-opened");
@@ -1179,7 +1179,8 @@ void WebContents::OpenDevTools(mate::Arguments* args) {
   std::string state;
   if (type_ == WEB_VIEW || !owner_window()) {
     state = "detach";
-  } else if (args && args->Length() == 1) {
+  }
+  if (args && args->Length() == 1) {
     bool detach = false;
     mate::Dictionary options;
     if (args->GetNext(&options)) {
diff --git a/docs/api/web-contents.md b/docs/api/web-contents.md
index 4def99b9e16c..1a346c968815 100644
--- a/docs/api/web-contents.md
+++ b/docs/api/web-contents.md
@@ -1144,6 +1144,9 @@ app.once('ready', () => {
 
 Opens the devtools.
 
+When `contents` is a `<webview>` tag, the `mode` would be `detach` by default,
+explicitly passing an empty `mode` can force using last used dock state.
+
 #### `contents.closeDevTools()`
 
 Closes the devtools.