diff --git a/README.md b/README.md
index 6a602cd..087bac7 100644
--- a/README.md
+++ b/README.md
@@ -2,12 +2,14 @@ I am really poor and I really can't afford a license. I just want to get rid of
 
 ## Features
 
-* Works for any version >=5 (we've tested this from 5.3 to 6.0 without any changes in the code)
-* Supports Proxmox VE and Proxmox Mail Gateway
+* Works for:
+    - Proxmox VE (5.x or later, tested up to 7.0)
+    - Proxmox Mail Gateway (5.x or later)
+    - Proxmox Backup Server (1.x)
 * Non-intrusive, no changes to any system file, persists between system updates
 * Comes with standard Debian package, easy to manage and automate
 * You can uninstall at any time, hassle-free
-* **No JavaScript**
+* **No JavaScript is involved** in the whole process
 
 ## Installation
 
diff --git a/scripts/purge b/scripts/purge
index 0c49f11..9b7d69b 100755
--- a/scripts/purge
+++ b/scripts/purge
@@ -1,2 +1,3 @@
 rm -f /etc/subscription
-rm -f /etc/pmg/subscription
\ No newline at end of file
+rm -f /etc/pmg/subscription
+rm -f /etc/proxmox-backup/subscription
\ No newline at end of file
diff --git a/usr/bin/pve-fake-subscription b/usr/bin/pve-fake-subscription
index 5263266..c450980 100755
--- a/usr/bin/pve-fake-subscription
+++ b/usr/bin/pve-fake-subscription
@@ -13,14 +13,14 @@ from typing import List
 from datetime import datetime, timedelta
 
 # PVE & PMG: /usr/share/perl5/PVE/Subscription.pm
-# PBS: /usr/lib/x86_64-linux-gnu/proxmox-backup/*
+# PBS: /usr/lib/x86_64-linux-gnu/proxmox-backup/* (source code at `https://git.proxmox.com/git/proxmox-backup.git`)
 shared_key_data = "kjfdlskfhiuewhfk947368"
 server_key_file = "/etc/ssh/ssh_host_rsa_key.pub"
 
 def get_timestamp() -> int:
     return int(time.time())
 
-# Perl's md5_base64_perl implementation
+# Perl's md5_base64 implementation
 def md5_base64_perl(x: str) -> str: 
     return base64.b64encode(hashlib.md5(x.encode()).digest()).strip(b'=').decode()
 
@@ -89,7 +89,7 @@ def generate_subscription_pbs(key: str, server_ids: List[str]) -> str:
 
     return key + "\n" + csum + "\n" + data + "\n"
 
-# key_pattern can be find in src/tools/subscription.rs
+# Key pattern: pbst-xxxxxxxxxx
 def activate_pbs(key: str, subscription_file: str) -> None:
     # get machine ID
     server_id = ""