I am a French user, but I prefer to use the SL websites (main official site, marketplace...) in English. Part of the reason is that I have set up email filters so that emails (about sales mainly) from the marketplace are correctly categorized according to their subject etc.
So I use the "language" menu in the website to select English. It sticks to it, to some extent, but every now and then (when I return to the site) it switches back to French, and the emails from marketplace turn French again.
Can you make it so that language selection becomes permanent, until the next manual selection of a different language ?
Thanks