Here's how you'd be able to upload past that error:
1. Make sure your browser displays images.
on desktop or Android
). Then select the image you wanna upload. It is important that the image you wanna upload is DISPLAYED first. The error happens because ths image wasn't displayed first. Displaying the image before uploading is required for the so-called HTML5 File API to work.
2.b If you cannot use an updated browser, use a browser that can edit your User-agent then set to Desktop display. Then follow the rest of the instructions (select image, wait to be displayed, before clicking UPLOAD).
Note that either way, you must use Desktop view / Desktop user-agent as much as possible.