diff --git a/js/modules/k6/browser/tests/browser_context_test.go b/js/modules/k6/browser/tests/browser_context_test.go
index 3779e959b00..274e4bcba9b 100644
--- a/js/modules/k6/browser/tests/browser_context_test.go
+++ b/js/modules/k6/browser/tests/browser_context_test.go
@@ -5,8 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"net/http/httptest"
-	"os"
 	"testing"
 	"time"
 
@@ -684,17 +682,7 @@ func TestK6Object(t *testing.T) {
 func TestNewTab(t *testing.T) {
 	t.Parallel()
 
-	// Start a server that will return static html files.
-	mux := http.NewServeMux()
-	s := httptest.NewServer(mux)
-	t.Cleanup(s.Close)
-
-	const (
-		slash = string(os.PathSeparator) //nolint:forbidigo
-		path  = slash + testBrowserStaticDir + slash
-	)
-	fs := http.FileServer(http.Dir(testBrowserStaticDir))
-	mux.Handle(path, http.StripPrefix(path, fs))
+	tb := newTestBrowser(t, withFileServer())
 
 	// Start the iteration
 	vu, _, _, cleanUp := startIteration(t, env.ConstLookup(env.K6TestRunID, "12345"))
@@ -703,11 +691,11 @@ func TestNewTab(t *testing.T) {
 	// Run the test script
 	_, err := vu.RunAsync(t, `
 		const p = await browser.newPage()
-		await p.goto("%s/%s/ping.html")
+		await p.goto("%s")
 
 		const p2 = await browser.context().newPage()
-		await p2.goto("%s/%s/ping.html")
-	`, s.URL, testBrowserStaticDir, s.URL, testBrowserStaticDir)
+		await p2.goto("%s")
+	`, tb.staticURL("ping.html"), tb.staticURL("ping.html"))
 	require.NoError(t, err)
 }
 
diff --git a/js/modules/k6/browser/tests/page_test.go b/js/modules/k6/browser/tests/page_test.go
index 669689951ec..a4ac5f9c2c0 100644
--- a/js/modules/k6/browser/tests/page_test.go
+++ b/js/modules/k6/browser/tests/page_test.go
@@ -8,8 +8,6 @@ import (
 	"image/png"
 	"io"
 	"net/http"
-	"net/http/httptest"
-	"os"
 	"runtime"
 	"strconv"
 	"sync/atomic"
@@ -675,7 +673,7 @@ func TestPageScreenshotFullpage(t *testing.T) {
 		const div = document.createElement('div');
 		div.style.width = '1280px';
 		div.style.height = '800px';
-		div.style.background = 'linear-gradient(red, blue)';
+		div.style.background = 'linear-gradient(to bottom, red, blue)';
 
 		document.body.appendChild(div);
 	}`)
@@ -690,15 +688,16 @@ func TestPageScreenshotFullpage(t *testing.T) {
 	img, err := png.Decode(reader)
 	assert.Nil(t, err)
 
-	assert.Equal(t, 1280, img.Bounds().Max.X, "screenshot width is not 1280px as expected, but %dpx", img.Bounds().Max.X)
-	assert.Equal(t, 800, img.Bounds().Max.Y, "screenshot height is not 800px as expected, but %dpx", img.Bounds().Max.Y)
+	assert.Equal(t, 1280, img.Bounds().Max.X, "want: screenshot width is 1280px, got: %dpx", img.Bounds().Max.X)
+	assert.Equal(t, 800, img.Bounds().Max.Y, "want: screenshot height is 800px, got: %dpx", img.Bounds().Max.Y)
 
+	// Allow tolerance to account for differences in rendering between
+	// different platforms and browsers. The goal is to ensure that the
+	// screenshot is mostly red at the top and mostly blue at the bottom.
 	r, _, b, _ := img.At(0, 0).RGBA()
-	assert.Greater(t, r, uint32(128))
-	assert.Less(t, b, uint32(128))
+	assert.Truef(t, r > b*2, "want: the top pixel to be dominantly red, got R: %d, B: %d", r, b)
 	r, _, b, _ = img.At(0, 799).RGBA()
-	assert.Less(t, r, uint32(128))
-	assert.Greater(t, b, uint32(128))
+	assert.Truef(t, b > r*2, "want: the bottom pixel to be dominantly blue, got R: %d, B: %d", r, b)
 }
 
 func TestPageTitle(t *testing.T) {
@@ -1757,17 +1756,7 @@ func TestShadowDOMAndDocumentFragment(t *testing.T) {
 		t.Skip() // timeouts
 	}
 
-	// Start a server that will return static html files.
-	mux := http.NewServeMux()
-	s := httptest.NewServer(mux)
-	t.Cleanup(s.Close)
-
-	const (
-		slash = string(os.PathSeparator) //nolint:forbidigo
-		path  = slash + testBrowserStaticDir + slash
-	)
-	fs := http.FileServer(http.Dir(testBrowserStaticDir))
-	mux.Handle(path, http.StripPrefix(path, fs))
+	tb := newTestBrowser(t, withFileServer())
 
 	tests := []struct {
 		name     string
@@ -1805,7 +1794,7 @@ func TestShadowDOMAndDocumentFragment(t *testing.T) {
 
 			got := vu.RunPromise(t, `
 				const p = await browser.newPage()
-				await p.goto("%s/%s/shadow_and_doc_frag.html")
+				await p.goto("%s")
 
 				const s = p.locator('%s')
 				await s.waitFor({
@@ -1815,7 +1804,7 @@ func TestShadowDOMAndDocumentFragment(t *testing.T) {
 
 				const text = await s.innerText();
 				return text;
- 			`, s.URL, testBrowserStaticDir, tt.selector)
+ 			`, tb.staticURL("shadow_and_doc_frag.html"), tt.selector)
 			assert.Equal(t, tt.want, got.Result().String())
 		})
 	}
diff --git a/js/modules/k6/browser/tests/test_browser.go b/js/modules/k6/browser/tests/test_browser.go
index ee3946d733d..d9464cd1b05 100644
--- a/js/modules/k6/browser/tests/test_browser.go
+++ b/js/modules/k6/browser/tests/test_browser.go
@@ -184,7 +184,7 @@ func (b *testBrowser) withFileServer() *testBrowser {
 
 	fs := http.FileServer(http.Dir(testBrowserStaticDir))
 
-	return b.withHandler(path, http.StripPrefix(path, fs).ServeHTTP)
+	return b.withHandler("/"+testBrowserStaticDir+"/", http.StripPrefix(path, fs).ServeHTTP)
 }
 
 // withHandler adds the given handler to the HTTP test server and makes it