Use Kee on Manuscriptcentral

How can I use Kee to save my credentials on https://mc.manuscriptcentral.com/lstm ? There is some pesky Javascript that “enhances” the form; if I turn off Javascript for that page Kee can fill in the password, but then the Log In button does not work anymore.

I have already contacted the website support, and they confirm that they do not have an accessible version (I am not sure how legal that is, but that’s how things are unfortunately).

Thanks!