Firstly, UFile no longer creates a .mrq file, period (the UFile support person told me that). Regarding the popup that comes up after pressing the Submit button, the solution is to exit your password manager before pressing the Submit button and then all will be well (the popup will be automatically filled out properly). If that doesn't work for you, exit your password manager before logging into UFile. I hope that helps someone...
How can I download the .mrq file in order to submit to Revenue Quebec? That option is no longer available. I tried clicking on the Netfile Quebec link that's on the "Tax Return" page, but the popup that comes up is erroniously filled in and I'm unable to type or delete in the fields (name/SIN/date of birth). In brief, I can't find a way to submit my Quebec return. Thanks for your help. Rupert