How to mount a LUKS encrypted partition at the moment of user login in Ubuntu 18.04?

Question

ubuntu

Colleagues, help me deal with LUKS in Ubuntu:
in 16.04, the user folder was encrypted and everything was fine. When a user authorized via ssh, console or graphical shell, the disk was connected on the fly.
But in version 18.06, they switched to encrypting the entire partition. As a result, a password is required during the boot phase and it is not possible to start the system remotely.
Created a separate partition for important files and mounted it to a folder inside the user folder. But the system suggests either automatically mounting it at boot (for this, you need to put the password in etc, after which encryption loses its meaning), or run the Disk utility manually every time and unlock the partition through it.
Tried to do it via cryptsetup open by putting it in ~/.bashrc, but it doesn't work for gnome login, but the connection happens every time the console window is opened.
Advise on how to mount a partition the first time you log into gnome, before other user autoloads start, such as the cloud sync utility.