Wow! Amazed / shocked (kinda) that this should be an issue in this day and age and all.
Orbmiser wrote:One of the reasons I moved to KDE as it does have that built in. Right click title bar and have the option For Special actions for Applications & windows with checking of "Remember Size & Position".
Thanks for that tip! While it's a rather cumbersome thing to do, at least for the first time or when one want to change that position, at least it is possible! Also, it seems I choose the right WM / DM (?) -manager then

I'm a first-time Mint user, but comes from Ubuntu using gnome since a few years.
I have to say that I've only been using Mint for like a couple of days, and already KDE's method seems to grow on me - set a few windows to remember a position, and others automatically finds the best (ish) spot around.