various fixes for fprintd and AUR packages

infrastructure/graduated/arch/README.md

@@ -742,16 +742,15 @@ You can create chroot environments to run firejails or just use for testing purp
 1. `pacman -S fprintd`
 2. `systemctl enable --now fprintd`
 3. `fprintd-enroll ducoterra`
-4. ~~Enable fingerprint terminal login but prompt for password first (enter switches to prompt for fingerprint)~~
+4. Install <https://aur.archlinux.org/pam-fprint-grosshack.git> to use fingerprint with gnome
 
-    DON'T DO THIS <https://wiki.archlinux.org/title/Fprint#Login_configuration>
+In order to use fingerprint auth with gnome for privileged system stuff with gdm,
+edit `/etc/pam.d/system-auth` and add the following to the top of the file:
 
-    /etc/pam.d/sudo
-
-    ```conf
-    # fingerprint auth
-    auth      sufficient pam_fprintd.so
-    ```
+```conf
+auth        sufficient      pam_fprintd_grosshack.so
+auth        sufficient      pam_unix.so try_first_pass nullok
+```
 
 ##### Turn Off Fingerprint When Laptop Lid Closed