>>530226520
https://github.com/ValveSoftware/steam-for-linux/issues/9640
What distro are you running? Is Steam installed via flatpak? you might need to give it access to other storage devices, or just install the native package (eg sudo pacman -S steam, assuming you're on arch/endeavour/cachyos).
Also check the link, seem like installing xdg-desktop-portal might help, there's also:
>Open with steam steam://open/console
>Then type in library_folder_add <path>
Or
>Steam > Settings > Interface
>and tick "Enable context menu focus compatibility mode"