Bug 1825573 - Make the visibility of the about:preferences migration wizard something we can control via Nimbus. r=settings-reviewers,mstriemer

Differential Revision: https://phabricator.services.mozilla.com/D174131

browser/app/profile/firefox.js

@@ -2197,6 +2197,7 @@ pref("browser.migrate.history.maxAgeInDays", 180);
 pref("browser.migrate.interactions.bookmarks", false);
 pref("browser.migrate.interactions.history", false);
 pref("browser.migrate.interactions.passwords", false);
+pref("browser.migrate.preferences-entrypoint.enabled", true);
 
 pref("extensions.pocket.api", "api.getpocket.com");
 pref("extensions.pocket.bffApi", "firefox-api-proxy.cdn.mozilla.net");

browser/themes/shared/preferences/preferences.css

@@ -246,6 +246,12 @@ checkbox {
   font-weight: 600;
 }
 
+@supports not -moz-bool-pref("browser.migrate.preferences-entrypoint.enabled") {
+  #dataMigrationGroup {
+    display: none;
+  }
+}
+
 #browserContainersExtensionContent {
   padding-block: 5px;
 }

toolkit/components/nimbus/FeatureManifest.yaml

@@ -1160,6 +1160,7 @@ migrationWizard:
   description: Prefs to control the Migration Wizard UI.
   owner: mconley@mozilla.com
   hasExposure: false
+  isEarlyStartup: true
   variables:
     useNewWizard:
       description: True if the "Variant 2" of the Migration Wizard browser / profile selection UI should be used.
@@ -1169,6 +1170,10 @@ migrationWizard:
       description: True if the "Variant 2" of the Migration Wizard browser / profile selection UI should be used. This is only meaningful in the new Migration Wizard.
       type: boolean
       setPref: browser.migrate.content-modal.import-all.enabled
+    showPreferencesEntrypoint:
+      description: True if an entrypoint to the migration wizard should be visible in about:preferences.
+      type: boolean
+      setPref: browser.migrate.preferences-entrypoint.enabled
 
 mixedContentUpgrading:
   description: Prefs to control whether we upgrade mixed passive content (images, audio, video) from http to https