diff --git a/Casks/discord-presence-relay.rb b/Casks/discord-presence-relay.rb
index 42d78f1..4f8d204 100644
--- a/Casks/discord-presence-relay.rb
+++ b/Casks/discord-presence-relay.rb
@@ -8,7 +8,7 @@ cask "discord-presence-relay" do
   homepage "https://github.com/YuzuZensai/Discord-RPC-Relay"
 
   auto_updates false
-  depends_on macos: ">= :big_sur"
+  depends_on macos: :big_sur
 
   app "Discord Presence Relay.app"
 
@@ -27,7 +27,7 @@ cask "discord-presence-relay" do
   caveats do
     <<~EOS
       #{token} is not notarized. The quarantine attribute is cleared
-      automatically on install; if macOS still refuses to open it
+      automatically on install, if macOS still refuses to open it
       ("app is damaged and can't be opened"), run:
         xattr -cr "#{appdir}/Discord Presence Relay.app"
     EOS
diff --git a/README.md b/README.md
index e48c6b8..054be45 100644
--- a/README.md
+++ b/README.md
@@ -52,9 +52,13 @@ settings once it's running.
 
 ```bash
 brew tap yuzuzensai/discord-rpc-relay https://github.com/YuzuZensai/Discord-RPC-Relay
+brew trust yuzuzensai/discord-rpc-relay
 brew install --cask discord-presence-relay
 ```
 
+`brew trust` is required once per tap, Homebrew blocks installing from
+third-party taps until you explicitly trust them.
+
 The cask clears the Gatekeeper quarantine attribute automatically after
 install, so the app opens normally right away.