Ooops, it seems that you ran into Firefox bug #1864296. Maybe you have more luck by restarting Firefox and not opening the Firefox developer tools. If you have the option, try another browser - it runs a lot faster in Chromium based browsers.

Select file to transfer in (`?`)

Select disk image

Select kernel file

Select file to transfer in (`?`)

Select disk image

Select kernel file

Select file to transfer in (?)

Select file to transfer in (`?`)