diff --git a/v2/pkg/protocols/headless/engine/page.go b/v2/pkg/protocols/headless/engine/page.go
index 7c7ad1cc..dbe9935f 100644
--- a/v2/pkg/protocols/headless/engine/page.go
+++ b/v2/pkg/protocols/headless/engine/page.go
@@ -3,6 +3,7 @@ package engine
 import (
 	"net/url"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/go-rod/rod"
@@ -11,11 +12,12 @@ import (
 
 // Page is a single page in an isolated browser instance
 type Page struct {
-	page     *rod.Page
-	rules    []requestRule
-	instance *Instance
-	router   *rod.HijackRouter
-	History  []HistoryData
+	page         *rod.Page
+	rules        []requestRule
+	instance     *Instance
+	router       *rod.HijackRouter
+	historyMutex sync.RWMutex
+	History      []HistoryData
 }
 
 // HistoryData contains the page request/response pairs
@@ -92,6 +94,9 @@ func (p *Page) URL() string {
 
 // DumpHistory returns the full page navigation history
 func (p *Page) DumpHistory() string {
+	p.historyMutex.RLock()
+	defer p.historyMutex.RUnlock()
+
 	var historyDump strings.Builder
 	for _, historyData := range p.History {
 		historyDump.WriteString(historyData.RawRequest)
@@ -99,3 +104,11 @@ func (p *Page) DumpHistory() string {
 	}
 	return historyDump.String()
 }
+
+// addToHistory adds a request/response pair to the page history
+func (p *Page) addToHistory(historyData HistoryData) {
+	p.historyMutex.Lock()
+	defer p.historyMutex.Unlock()
+
+	p.History = append(p.History, historyData)
+}
diff --git a/v2/pkg/protocols/headless/engine/rules.go b/v2/pkg/protocols/headless/engine/rules.go
index 17b66ee4..5aa0c91d 100644
--- a/v2/pkg/protocols/headless/engine/rules.go
+++ b/v2/pkg/protocols/headless/engine/rules.go
@@ -64,9 +64,11 @@ func (p *Page) routingRuleHandler(ctx *rod.Hijack) {
 	var rawResp strings.Builder
 	respPayloads := ctx.Response.Payload()
 	if respPayloads != nil {
-		rawResp.WriteString(fmt.Sprintf("HTTP/1.1 %d %s\n", respPayloads.ResponseCode, respPayloads.ResponsePhrase))
+		rawResp.WriteString("HTTP/1.1 ")
+		rawResp.WriteString(fmt.Sprint(respPayloads.ResponseCode))
+		rawResp.WriteString(" " + respPayloads.ResponsePhrase + "+\n")
 		for _, header := range respPayloads.ResponseHeaders {
-			rawResp.WriteString(fmt.Sprintf("%s: %s\n", header.Name, header.Value))
+			rawResp.WriteString(header.Name + ": " + header.Value + "\n")
 		}
 		rawResp.WriteString("\n")
 		rawResp.WriteString(ctx.Response.Body())
@@ -77,5 +79,5 @@ func (p *Page) routingRuleHandler(ctx *rod.Hijack) {
 		RawRequest:  rawReq,
 		RawResponse: rawResp.String(),
 	}
-	p.History = append(p.History, historyData)
+	p.addToHistory(historyData)
 }