After trying various links, both in the post above and from my own searches, I discovered that I could Google "Yahoo Mail UK" which took me to the log-in page and then I could access my email.
I deleted the existing Yahoo bookmark, logged in manually and then bookmarked that.
https://www.new-car-discount.com/car/ford/capri-estate/4x4/electric/automatic/125kw-style-52kwh-5dr-auto/25/ £33,333 - still have 5 years of stupid ...