I don't understand how to contribute to fix OCR errors. Even after registering and logging in, after searching a word and clicking on the image, then getting th

I don't understand how to contribute to fix OCR errors. Even after registering and logging in, after searching a word and clicking on the image, then getting the annotation in the viewer, it does not show the "Edit | Confirm" buttons as they appear in the screenshot from the documentation. So I can see the annotation and its automatic transcriptions, but I can neither edit nor confirm it.