- Electron version: v0.36.9
- Operating system: Windows 10/OS X

In #779 a `disposition` was added to the `new-window` event in [webContents](https://github.com/atom/electron/blob/master/docs/api/web-contents.md#event-new-window) but it always seems to be set to `new-window` when clicking on target="_blank" links in our web app wrapper: https://github.com/irccloud/irccloud-desktop/blob/v0.1.3/app/main.js#L109

If I Ctrl (Win) or Cmd (OS X) or middle click on links, I would expect to see a `background-tab` disposition, as in Chrome that will open links in a background tab, while keeping focus on the current tab. I'd like to catch this behaviour to set `activate` to false in `shell.openExternal`.

Is this possible?

atom/browser/api/atom_api_app.cc
v8::Local<v8::Context> context, void* priv) {
  v8::Isolate* isolate = context->GetIsolate();
  auto command_line = base::CommandLine::ForCurrentProcess();
  mate::Dictionary dict(isolate, exports);
  dict.Set("app", atom::api::App::Create(isolate));
  dict.SetMethod("appendSwitch", &AppendSwitch);
  dict.SetMethod("appendArgument",
                 base::Bind(&base::CommandLine::AppendArg,
                            base::Unretained(command_line)));
#if defined(OS_MACOSX)
  auto browser = base::Unretained(Browser::Get());
  dict.SetMethod("dockBounce", &DockBounce);
  dict.SetMethod("dockCancelBounce",
                 base::Bind(&Browser::DockCancelBounce, browser));
  dict.SetMethod("dockSetBadgeText",
                 base::Bind(&Browser::DockSetBadgeText, browser));
  dict.SetMethod("dockGetBadgeText",
                 base::Bind(&Browser::DockGetBadgeText, browser));
  dict.SetMethod("dockHide", base::Bind(&Browser::DockHide, browser));
  dict.SetMethod("dockShow", base::Bind(&Browser::DockShow, browser));
  dict.SetMethod("dockSetMenu", &DockSetMenu);
  dict.SetMethod("dockSetIcon", base::Bind(&Browser::DockSetIcon, browser));
#endif
}
}  
NODE_MODULE_CONTEXT_AWARE_BUILTIN(atom_browser_app, Initialize)