The EditEADRequest.html form doesn't work with web validation in the default web pages.
Submit an EAD request, or update an existing non-photoduplication request's WebRequestForm field to EADRequest.
Add a validation rule for the AeonForm specified in EditEADRequest.html, which should be EditGenericRequestEAD.
Edit the request and submit values that will fail web validation.
You will get a 'File not found' error, because it's trying to return you to the from 'EditGenericRequestEAD.html' which does not exist. Changing the AeonForm field to EditEADRequest does not work either; in that case you will simply get a blank page instead of the file-not-found error.
Released in Aeon 4.0