diff --git a/app/src/main/java/org/mozilla/fenix/ext/StrictMode.kt b/app/src/main/java/org/mozilla/fenix/ext/StrictMode.kt
deleted file mode 100644
index 54985108fe..0000000000
--- a/app/src/main/java/org/mozilla/fenix/ext/StrictMode.kt
+++ /dev/null
@@ -1,28 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-package org.mozilla.fenix.ext
-
-import android.os.StrictMode
-import mozilla.components.support.ktx.android.os.resetAfter
-import org.mozilla.fenix.Config
-
-/**
- * Runs the given [functionBlock] and sets the ThreadPolicy after its completion in Debug mode.
- * Otherwise simply runs the [functionBlock]
- * This function is written in the style of [AutoCloseable.use].
- * @return the value returned by [functionBlock].
- */
-inline fun <R> StrictMode.ThreadPolicy.resetPoliciesAfter(functionBlock: () -> R): R {
-    // Calling resetAfter takes 1-2ms (unknown device) so we only execute it if StrictMode can
-    // actually be enabled. https://github.com/mozilla-mobile/fenix/issues/11617
-    //
-    // The expression in this if is duplicated in StrictModeManager.enableStrictMode: see that method
-    // for details.
-    return if (Config.channel.isDebug) {
-        resetAfter { functionBlock() }
-    } else {
-        functionBlock()
-    }
-}
diff --git a/app/src/test/java/org/mozilla/fenix/StrictModeManagerTest.kt b/app/src/test/java/org/mozilla/fenix/StrictModeManagerTest.kt
index 61a14ef1f1..f4f3e21a81 100644
--- a/app/src/test/java/org/mozilla/fenix/StrictModeManagerTest.kt
+++ b/app/src/test/java/org/mozilla/fenix/StrictModeManagerTest.kt
@@ -16,6 +16,8 @@ import io.mockk.slot
 import io.mockk.unmockkStatic
 import io.mockk.verify
 import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Assert.fail
 import org.junit.Before
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -73,4 +75,42 @@ class StrictModeManagerTest {
         callbacks.captured.onFragmentResumed(fragmentManager, mockk())
         verify { fragmentManager.unregisterFragmentLifecycleCallbacks(callbacks.captured) }
     }
+
+    @Test
+    fun `GIVEN we're in a release build WHEN resetAfter is called THEN we return the value from the function block`() {
+        val expected = "Hello world"
+        val actual = releaseManager.resetAfter(StrictMode.allowThreadDiskReads()) { expected }
+        assertEquals(expected, actual)
+    }
+
+    @Test
+    fun `GIVEN we're in a debug build WHEN resetAfter is called THEN we return the value from the function block`() {
+        val expected = "Hello world"
+        val actual = debugManager.resetAfter(StrictMode.allowThreadDiskReads()) { expected }
+        assertEquals(expected, actual)
+    }
+
+    @Test
+    fun `GIVEN we're in a release build WHEN resetAfter is called THEN the old policy is not set`() {
+        releaseManager.resetAfter(StrictMode.allowThreadDiskReads()) { "" }
+        verify(exactly = 0) { StrictMode.setThreadPolicy(any()) }
+    }
+
+    @Test
+    fun `GIVEN we're in a debug build WHEN resetAfter is called THEN the old policy is set`() {
+        val expectedPolicy = StrictMode.allowThreadDiskReads()
+        debugManager.resetAfter(expectedPolicy) { "" }
+        verify { StrictMode.setThreadPolicy(expectedPolicy) }
+    }
+
+    @Test
+    fun `GIVEN we're in a debug build WHEN resetAfter is called and an exception is thrown from the function THEN the old policy is set`() {
+        val expectedPolicy = StrictMode.allowThreadDiskReads()
+        try {
+            debugManager.resetAfter(expectedPolicy) { throw IllegalStateException() }
+            @Suppress("UNREACHABLE_CODE") fail("Expected previous method to throw.")
+        } catch (e: IllegalStateException) { /* Do nothing */ }
+
+        verify { StrictMode.setThreadPolicy(expectedPolicy) }
+    }
 }
diff --git a/app/src/test/java/org/mozilla/fenix/ext/StrictModeTest.kt b/app/src/test/java/org/mozilla/fenix/ext/StrictModeTest.kt
deleted file mode 100644
index 26854c46d5..0000000000
--- a/app/src/test/java/org/mozilla/fenix/ext/StrictModeTest.kt
+++ /dev/null
@@ -1,79 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-package org.mozilla.fenix.ext
-
-import android.os.StrictMode
-import io.mockk.Runs
-import io.mockk.every
-import io.mockk.just
-import io.mockk.mockk
-import io.mockk.mockkObject
-import io.mockk.mockkStatic
-import io.mockk.unmockkObject
-import io.mockk.unmockkStatic
-import io.mockk.verify
-import org.junit.After
-import org.junit.Assert.assertEquals
-import org.junit.Assert.assertNotNull
-import org.junit.Before
-import org.junit.Test
-import org.junit.runner.RunWith
-import org.mozilla.fenix.Config
-import org.mozilla.fenix.ReleaseChannel
-import org.mozilla.fenix.helpers.FenixRobolectricTestRunner
-
-@RunWith(FenixRobolectricTestRunner::class)
-class StrictModeTest {
-
-    private lateinit var threadPolicy: StrictMode.ThreadPolicy
-    private lateinit var functionBlock: () -> String
-
-    @Before
-    fun setup() {
-        threadPolicy = StrictMode.ThreadPolicy.LAX
-        functionBlock = mockk()
-        mockkStatic(StrictMode::class)
-        mockkObject(Config)
-
-        every { StrictMode.setThreadPolicy(threadPolicy) } just Runs
-        every { functionBlock() } returns "Hello world"
-    }
-
-    @After
-    fun teardown() {
-        unmockkStatic(StrictMode::class)
-        unmockkObject(Config)
-    }
-
-    @Test
-    fun `runs function block in release`() {
-        every { Config.channel } returns ReleaseChannel.Release
-        assertEquals("Hello world", threadPolicy.resetPoliciesAfter(functionBlock))
-        verify(exactly = 0) { StrictMode.setThreadPolicy(any()) }
-    }
-
-    @Test
-    fun `runs function block in debug`() {
-        every { Config.channel } returns ReleaseChannel.Debug
-        assertEquals("Hello world", threadPolicy.resetPoliciesAfter(functionBlock))
-        verify { StrictMode.setThreadPolicy(threadPolicy) }
-    }
-
-    @Test
-    fun `sets thread policy even if function throws`() {
-        every { Config.channel } returns ReleaseChannel.Debug
-        every { functionBlock() } throws IllegalStateException()
-        var exception: IllegalStateException? = null
-
-        try {
-            threadPolicy.resetPoliciesAfter(functionBlock)
-        } catch (e: IllegalStateException) {
-            exception = e
-        }
-
-        verify { StrictMode.setThreadPolicy(threadPolicy) }
-        assertNotNull(exception)
-    }
-}