diff --git a/src/browser/register.ts b/src/browser/register.ts
index 1079d159..e99d64c6 100644
--- a/src/browser/register.ts
+++ b/src/browser/register.ts
@@ -4,12 +4,12 @@ import "./pages/error.css"
 import "./pages/global.css"
 import "./pages/login.css"
 
-async function registerServiceWorker(): Promise<void> {
+export async function registerServiceWorker(): Promise<void> {
   const options = getOptions()
   const path = normalize(`${options.csStaticBase}/dist/serviceWorker.js`)
   try {
     await navigator.serviceWorker.register(path, {
-      scope: (options.base ?? "") + "/",
+      scope: options.base + "/",
     })
     console.log("[Service Worker] registered")
   } catch (error) {
diff --git a/test/unit/register.test.ts b/test/unit/register.test.ts
index d19f6300..b845aab5 100644
--- a/test/unit/register.test.ts
+++ b/test/unit/register.test.ts
@@ -1,5 +1,7 @@
 import { JSDOM } from "jsdom"
 import { loggerModule } from "../utils/helpers"
+import { registerServiceWorker } from "../../src/browser/register"
+import { LocationLike } from "./util.test"
 
 describe("register", () => {
   describe("when navigator and serviceWorker are defined", () => {
@@ -37,6 +39,12 @@ describe("register", () => {
       global.navigator = (undefined as unknown) as Navigator & typeof globalThis
       global.location = (undefined as unknown) as Location & typeof globalThis
     })
+    it("test should have access to browser globals from beforeAll", () => {
+      expect(typeof global.window).not.toBeFalsy()
+      expect(typeof global.document).not.toBeFalsy()
+      expect(typeof global.navigator).not.toBeFalsy()
+      expect(typeof global.location).not.toBeFalsy()
+    })
 
     it("should register a ServiceWorker", () => {
       // Load service worker like you would in the browser
@@ -84,4 +92,89 @@ describe("register", () => {
       expect(spy).toHaveBeenCalledWith("[Service Worker] navigator is undefined")
     })
   })
+  describe("registerServiceWorker", () => {
+    let serviceWorkerPath: string
+    let serviceWorkerScope: string
+    const mockFn = jest.fn((path: string, options: { scope: string }) => {
+      serviceWorkerPath = path
+      serviceWorkerScope = options.scope
+      return undefined
+    })
+
+    beforeAll(() => {
+      const location: LocationLike = {
+        pathname: "",
+        origin: "http://localhost:8080",
+      }
+      const { window } = new JSDOM()
+      global.window = (window as unknown) as Window & typeof globalThis
+      global.document = window.document
+      global.navigator = window.navigator
+      global.location = location as Location
+
+      Object.defineProperty(global.navigator, "serviceWorker", {
+        value: {
+          register: mockFn,
+        },
+      })
+    })
+
+    afterEach(() => {
+      mockFn.mockClear()
+      jest.resetModules()
+    })
+
+    afterAll(() => {
+      jest.restoreAllMocks()
+
+      // We don't want these to stay around because it can affect other tests
+      global.window = (undefined as unknown) as Window & typeof globalThis
+      global.document = (undefined as unknown) as Document & typeof globalThis
+      global.navigator = (undefined as unknown) as Navigator & typeof globalThis
+      global.location = (undefined as unknown) as Location & typeof globalThis
+    })
+    it("should register when options.base is undefined", async () => {
+      // Mock getElementById
+      const csStaticBasePath = "/static/development/Users/jp/Dev/code-server"
+      const spy = jest.spyOn(document, "getElementById")
+      // Create a fake element and set the attribute
+      const mockElement = document.createElement("div")
+      mockElement.id = "coder-options"
+      mockElement.setAttribute(
+        "data-settings",
+        `{"csStaticBase":"${csStaticBasePath}","logLevel":2,"disableTelemetry":false,"disableUpdateCheck":false}`,
+      )
+      // Return mockElement from the spy
+      // this way, when we call "getElementById"
+      // it returns the element
+      spy.mockImplementation(() => mockElement)
+
+      await registerServiceWorker()
+
+      expect(mockFn).toBeCalled()
+      expect(serviceWorkerPath).toMatch(`${csStaticBasePath}/dist/serviceWorker.js`)
+      expect(serviceWorkerScope).toMatch("/")
+    })
+    it("should register when options.base is defined", async () => {
+      const csStaticBasePath = "/static/development/Users/jp/Dev/code-server"
+      const spy = jest.spyOn(document, "getElementById")
+      // Create a fake element and set the attribute
+      const mockElement = document.createElement("div")
+      mockElement.id = "coder-options"
+      mockElement.setAttribute(
+        "data-settings",
+        `{"base":"proxy/","csStaticBase":"${csStaticBasePath}","logLevel":2,"disableTelemetry":false,"disableUpdateCheck":false}`,
+      )
+      // Return mockElement from the spy
+      // this way, when we call "getElementById"
+      // it returns the element
+      spy.mockImplementation(() => mockElement)
+
+      await registerServiceWorker()
+
+      expect(mockFn).toBeCalled()
+      expect(serviceWorkerPath).toMatch(`/dist/serviceWorker.js`)
+      expect(serviceWorkerScope).toMatch("/")
+    })
+  })
 })
diff --git a/test/unit/util.test.ts b/test/unit/util.test.ts
index 02f3fdc5..e4d6349a 100644
--- a/test/unit/util.test.ts
+++ b/test/unit/util.test.ts
@@ -16,7 +16,7 @@ import { loggerModule } from "../utils/helpers"
 const dom = new JSDOM()
 global.document = dom.window.document
 
-type LocationLike = Pick<Location, "pathname" | "origin">
+export type LocationLike = Pick<Location, "pathname" | "origin">
 
 // jest.mock is hoisted above the imports so we must use `require` here.
 jest.mock("@coder/logger", () => require("../utils/helpers").loggerModule)