[fractal/improve_secret_service_guide] docs: Improve runtime dependencies section

[Julian Sparber <jsparber src gnome org>]

commit 34ba8c374e3c60931f9789f4a367407f463731fb
Author: Julian Sparber <julian sparber net>
Date:   Mon Oct 17 11:13:57 2022 +0000

    docs: Improve runtime dependencies section
    
    This adds mention of `xdg-desktop-portal` since if it's not installed libsecret will fallback to the 
talking directly to SecretService which will fail inside flatpak.

 README.md | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
---
diff --git a/README.md b/README.md
index 35f562188..d0ca0a8ff 100644
--- a/README.md
+++ b/README.md
@@ -86,8 +86,7 @@ flatpak install --user gnome-nightly org.gnome.Fractal.Devel
 Fractal doesn't store your **password** but uses [Secret 
Service](https://www.freedesktop.org/wiki/Specifications/secret-storage-spec/)
 to store your **access token** and **passphrase** used to encrypt the local cache.
 Therefore, you need to have software providing that service on your system.
-If you're using GNOME this should work for you out of the box and gnome-keyring or ksecretservice
-should already be installed and setup.
+If you're using GNOME this should work. If you are using a different desktop enviroment or are facing issues 
make sure to have `xdg-desktop-portal` installed and a [Secret 
Service](https://www.freedesktop.org/wiki/Specifications/secret-storage-spec/) provider, for example 
`gnome-keyring` or KeepassXC ([setup guide](https://avaldes.co/2020/01/28/secret-service-keepassxc.html)).
 
 ## Security Best Practices