how to have SteamLibrary NOT in the app folder? (linux)

[Gene_DancingHamster]

ok, Linux Mint 19 Cinnamon, Steam is installed, want to have installed games (SteamLibrary) somewhere other than /home/<me>.

a) i tried moving steamapps and using a symlink to it: no joy, seems Steam won't follow the symlink.

b) i tried creating a new SteamLibrary via the Steam>Settings>Downloads>Steam Library Folders process but the new library turns out to be temporary (tmpfs), disappears when you exit Steam.

c) i tried creating a /home/SteamLibrary with right ownership and permissions and using it via ...>Steam Library Folders: no joy, /home/SteamLibrary is not seen in the Steam Library Folders dialog. (???)

d) i tried creating a SteamFolder on a new partition (same drive) with the right ownership and permissions, then mounted the partition as /mnt/<other drive>: no joy, /mnt is not listed within the ...>Steam Library Folders dialog. (wtf?)

e) saw somewhere that there is supposed to be a "Move Install Folder" option within each game's Properties>Local Files tab. tried that but no joy, there is no "Move Install Folder" option available on that Local Files tab.

f) i tried a variety of old (2016-) solutions proposed here: no joy.

so, any ideas how this is properly done?