diff --git a/browser/extensions/shield-recipe-client/lib/ShieldRecipeClient.jsm b/browser/extensions/shield-recipe-client/lib/ShieldRecipeClient.jsm
index 7498b8e1d2c2..ff3392a4fec1 100644
--- a/browser/extensions/shield-recipe-client/lib/ShieldRecipeClient.jsm
+++ b/browser/extensions/shield-recipe-client/lib/ShieldRecipeClient.jsm
@@ -42,6 +42,7 @@ const DEFAULT_PREFS = {
   first_run: true,
 };
 const PREF_DEV_MODE = "extensions.shield-recipe-client.dev_mode";
+const PREF_SELF_SUPPORT_ENABLED = "browser.selfsupport.enabled";
 const PREF_LOGGING_LEVEL = PREF_BRANCH + "logging.level";
 
 let log = null;
@@ -63,6 +64,16 @@ this.ShieldRecipeClient = {
     );
     log = LogManager.getLogger("bootstrap");
 
+    // Disable self-support, since we replace its behavior.
+    // Self-support only checks its pref on start, so if we disable it, wait
+    // until next startup to run, unless the dev_mode preference is set.
+    if (Preferences.get(PREF_SELF_SUPPORT_ENABLED, true)) {
+      Preferences.set(PREF_SELF_SUPPORT_ENABLED, false);
+      if (!Preferences.get(PREF_DEV_MODE, false)) {
+        return;
+      }
+    }
+
     // Initialize experiments first to avoid a race between initializing prefs
     // and recipes rolling back pref changes when experiments end.
     try {
@@ -76,6 +87,11 @@ this.ShieldRecipeClient = {
 
   shutdown(reason) {
     CleanupManager.cleanup();
+
+    // Re-enable self-support if we're being disabled.
+    if (reason === REASONS.ADDON_DISABLE || reason === REASONS.ADDON_UNINSTALL) {
+      Services.prefs.setBoolPref(PREF_SELF_SUPPORT_ENABLED, true);
+    }
   },
 
   setDefaultPrefs() {
diff --git a/browser/extensions/shield-recipe-client/test/browser/browser_ClientEnvironment.js b/browser/extensions/shield-recipe-client/test/browser/browser_ClientEnvironment.js
index a831afb4c45f..21ddd4381abe 100644
--- a/browser/extensions/shield-recipe-client/test/browser/browser_ClientEnvironment.js
+++ b/browser/extensions/shield-recipe-client/test/browser/browser_ClientEnvironment.js
@@ -116,9 +116,6 @@ add_task(async function testExperiments() {
 add_task(async function isFirstRun() {
   let environment = ClientEnvironment.getEnvironment();
 
-  // isFirstRun is set to false after the recipe client runs
-  ok(!environment.isFirstRun, "isFirstRun has a default value");
-
   // isFirstRun is read from a preference
   await SpecialPowers.pushPrefEnv({set: [["extensions.shield-recipe-client.first_run", true]]});
   environment = ClientEnvironment.getEnvironment();
diff --git a/testing/profiles/prefs_general.js b/testing/profiles/prefs_general.js
index bf2f780b701e..9059e0759e1e 100644
--- a/testing/profiles/prefs_general.js
+++ b/testing/profiles/prefs_general.js
@@ -321,7 +321,7 @@ user_pref("browser.search.countryCode", "US");
 user_pref("browser.search.geoSpecificDefaults", false);
 
 // Make sure Shield doesn't hit the network.
-user_pref("extensions.shield-recipe-client.api_url", "https://%(server)s/selfsupport-dummy/");
+user_pref("extensions.shield-recipe-client.api_url", "https://example.com/selfsupport-dummy/");
 
 user_pref("media.eme.enabled", true);