Testing focus() for file input fields

The following form is for testing the keyboard tabbing behavior of different form fields. Especially the <input type="file"> shows some strange behavior. Trying to set the focus on such field programmatically (see JavaScript below) doesn't seem to work across browsers. However, it does work with other input fiels, which you can try by uncommenting the second line in the JavaScript code.

window.onload = function(){

Strangely, using the input field's id as a named anchor, does work (when triggered by keyboard):

File Upload

Enter your name:

Upload the 1. file:

Check it out:

Upload the 2. file:

Radio activity:


Clicking this link will bring you back to the second file upload field!