diff --git a/app/src/main/java/org/mozilla/fenix/components/metrics/MetricController.kt b/app/src/main/java/org/mozilla/fenix/components/metrics/MetricController.kt
index f10182b46..4ebe8c8dc 100644
--- a/app/src/main/java/org/mozilla/fenix/components/metrics/MetricController.kt
+++ b/app/src/main/java/org/mozilla/fenix/components/metrics/MetricController.kt
@@ -223,7 +223,7 @@ internal class ReleaseMetricController(
             metadata?.get("enabled")?.let { enabledAddons ->
                 if (enabledAddons is List<*>) {
                     settings.enabledAddonsCount = enabledAddons.size
-                    settings.enabledAddonsList = enabledAddons.joinToString()
+                    settings.enabledAddonsList = enabledAddons.joinToString(",")
                 }
             }
 
diff --git a/app/src/test/java/org/mozilla/fenix/components/metrics/MetricControllerTest.kt b/app/src/test/java/org/mozilla/fenix/components/metrics/MetricControllerTest.kt
index 2a824564f..25bf2274e 100644
--- a/app/src/test/java/org/mozilla/fenix/components/metrics/MetricControllerTest.kt
+++ b/app/src/test/java/org/mozilla/fenix/components/metrics/MetricControllerTest.kt
@@ -15,11 +15,16 @@ import mozilla.components.support.base.Component
 import mozilla.components.support.base.facts.Action
 import mozilla.components.support.base.facts.Fact
 import mozilla.components.support.base.log.logger.Logger
+import mozilla.components.support.test.robolectric.testContext
 import mozilla.components.support.webextensions.facts.WebExtensionFacts
+import org.junit.Assert.assertEquals
 import org.junit.Before
 import org.junit.Test
+import org.junit.runner.RunWith
+import org.mozilla.fenix.helpers.FenixRobolectricTestRunner
 import org.mozilla.fenix.utils.Settings
 
+@RunWith(FenixRobolectricTestRunner::class)
 class MetricControllerTest {
 
     @MockK(relaxUnitFun = true) private lateinit var dataService1: MetricsService
@@ -338,7 +343,7 @@ class MetricControllerTest {
     @Test
     fun `web extension fact should set value in SharedPreference`() {
         val enabled = true
-        val settings: Settings = mockk(relaxed = true)
+        val settings = Settings(testContext)
         val controller = ReleaseMetricController(
             services = listOf(dataService1),
             isDataTelemetryEnabled = { enabled },
@@ -350,19 +355,19 @@ class MetricControllerTest {
             Action.INTERACTION,
             WebExtensionFacts.Items.WEB_EXTENSIONS_INITIALIZED,
             metadata = mapOf(
-                "installed" to listOf("test1"),
-                "enabled" to listOf("test2")
+                "installed" to listOf("test1", "test2", "test3", "test4"),
+                "enabled" to listOf("test2", "test4")
             )
         )
 
-        verify(exactly = 0) { settings.installedAddonsCount = any() }
-        verify(exactly = 0) { settings.installedAddonsList = any() }
-        verify(exactly = 0) { settings.enabledAddonsCount = any() }
-        verify(exactly = 0) { settings.enabledAddonsList = any() }
+        assertEquals(settings.installedAddonsCount, 0)
+        assertEquals(settings.installedAddonsList, "")
+        assertEquals(settings.enabledAddonsCount, 0)
+        assertEquals(settings.enabledAddonsList, "")
         controller.factToEvent(fact)
-        verify(exactly = 1) { settings.installedAddonsCount = any() }
-        verify(exactly = 1) { settings.installedAddonsList = any() }
-        verify(exactly = 1) { settings.enabledAddonsCount = any() }
-        verify(exactly = 1) { settings.enabledAddonsList = any() }
+        assertEquals(settings.installedAddonsCount, 4)
+        assertEquals(settings.installedAddonsList, "test1,test2,test3,test4")
+        assertEquals(settings.enabledAddonsCount, 2)
+        assertEquals(settings.enabledAddonsList, "test2,test4")
     }
 }