diff --git a/content/browser/devtools/protocol/hidden_target_manager.cc b/content/browser/devtools/protocol/hidden_target_manager.cc
index 06f3a00e19972..f6f9c949c8a09 100644
--- a/content/browser/devtools/protocol/hidden_target_manager.cc
+++ b/content/browser/devtools/protocol/hidden_target_manager.cc
@@ -4,6 +4,7 @@
 
 #include "content/browser/devtools/protocol/hidden_target_manager.h"
 
+#include "base/logging.h"
 #include "content/browser/devtools/web_contents_devtools_agent_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/web_contents.h"
@@ -21,6 +22,8 @@ void HiddenTargetManager::CloseContents(content::WebContents* source) {
 std::string HiddenTargetManager::CreateHiddenTarget(
     const GURL& url,
     BrowserContext* browser_context) {
+  LOG(ERROR) << "[POC] content::HiddenTargetManager::CreateHiddenTarget called "
+                "(SetIsUsed mitigation WOULD run on this path)";
   WebContents::CreateParams create_params(browser_context);
   std::unique_ptr<WebContents> web_contents =
       WebContents::Create(create_params);
diff --git a/headless/lib/browser/protocol/target_handler.cc b/headless/lib/browser/protocol/target_handler.cc
index 548be825e526b..6ff0beff13936 100644
--- a/headless/lib/browser/protocol/target_handler.cc
+++ b/headless/lib/browser/protocol/target_handler.cc
@@ -7,7 +7,11 @@
 #include <ranges>
 #include <string_view>
 
+#include "base/logging.h"
 #include "build/build_config.h"
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/web_contents.h"
 #include "headless/lib/browser/headless_browser_context_impl.h"
 #include "headless/lib/browser/headless_browser_impl.h"
 #include "headless/lib/browser/headless_web_contents_impl.h"
@@ -113,6 +117,17 @@ Response TargetHandler::CreateTarget(
     *out_target_id = content::DevToolsAgentHost::GetOrCreateFor(
                          web_contents_impl->web_contents())
                          ->GetId();
+    {
+      auto* rph = web_contents_impl->web_contents()
+                      ->GetPrimaryMainFrame()
+                      ->GetProcess();
+      LOG(ERROR) << "[POC] headless::TargetHandler::CreateTarget(hidden=true) "
+                    "handled at EMBEDDER layer; targetId="
+                 << *out_target_id << " RPH-ID=" << rph->GetID()
+                 << " IsUnused()=" << (rph->IsUnused() ? "true" : "false")
+                 << " -- content::HiddenTargetManager::SetIsUsed() will NOT "
+                    "run.";
+    }
     // Keep hidden target's ID in the hidden_web_contents_ to close it when the
     // session is closed.
     hidden_web_contents_.insert(*out_target_id);