Upload multiple files through a single file dialog?

In a Webform, I want to let the user upload multiple files via one call of the file dialog. I found the following modules.

  • Webform Multiple File Upload
  • Webform Multiple File

With either of them, I cannot open the file dialog once and select all the files. Instead, I need to open the file dialog again for every file.

Is there a way to allow file uploads in one go for Webform forms?