diff --git a/resources/web/guide/0/load.js b/resources/web/guide/0/load.js
index 03849f6388..8699420333 100644
--- a/resources/web/guide/0/load.js
+++ b/resources/web/guide/0/load.js
@@ -10,6 +10,11 @@ function OnInit()
 	// Orca: fallback timeout in case the C++ -> JS signal fails (e.g., WebKit issues).
 	// Jump to the target page after 3 minutes so slow computers don't get stuck on a partially loaded page.
 	setTimeout("JumpToTarget()",180*1000);
+
+	var tSend={};
+	tSend['sequence_id']=Math.round(new Date() / 1000);
+	tSend['command']="userguide_loading_page_ready";
+	SendWXMessage(JSON.stringify(tSend));
 }
 
 function HandleStudio( pVal )
diff --git a/src/slic3r/GUI/WebGuideDialog.cpp b/src/slic3r/GUI/WebGuideDialog.cpp
index 0c799c9d47..088d4d6c21 100644
--- a/src/slic3r/GUI/WebGuideDialog.cpp
+++ b/src/slic3r/GUI/WebGuideDialog.cpp
@@ -450,6 +450,16 @@ void GuideFrame::on_profile_loaded()
     SaveProfileData();
     const std::string strAll = m_ProfileJson.dump(-1, ' ', false, json::error_handler_t::ignore);
     BOOST_LOG_TRIVIAL(info) << __FUNCTION__ << ", finished, json contents:\n" << strAll;
+    m_profile_ready = true;
+    notify_profile_loaded();
+}
+
+// The data is often ready before the loading page has run its scripts, and a
+// call into a page without HandleStudio is lost, so the message waits for both.
+void GuideFrame::notify_profile_loaded()
+{
+    if (!m_profile_ready || !m_page_ready)
+        return;
     json res;
     res["command"]     = "userguide_profile_load_finish";
     res["sequence_id"] = "10001";
@@ -545,7 +555,11 @@ void GuideFrame::OnScriptMessage(wxWebViewEvent &evt)
         wxString strCmd = j["command"];
         BOOST_LOG_TRIVIAL(trace) << "GuideFrame::OnScriptMessage;Command:" << strCmd;
 
-        if (strCmd == "close_page") {
+        if (strCmd == "userguide_loading_page_ready") {
+            m_page_ready = true;
+            notify_profile_loaded();
+        }
+        else if (strCmd == "close_page") {
             this->EndModal(wxID_CANCEL);
         }
         if (strCmd == "user_clause") {
diff --git a/src/slic3r/GUI/WebGuideDialog.hpp b/src/slic3r/GUI/WebGuideDialog.hpp
index 3f84f4248f..8853ee2661 100644
--- a/src/slic3r/GUI/WebGuideDialog.hpp
+++ b/src/slic3r/GUI/WebGuideDialog.hpp
@@ -102,6 +102,7 @@ public:
     int LoadProfileFamily(std::string strVendor, std::string strFilePath);
     void init_guide_paths();
     void on_profile_loaded();
+    void notify_profile_loaded();
     bool BuildProfileJson(const PresetBundle& bundle, bool require_all_resource_vendors);
     bool BuildProfileDataFromPresetBundle();
     bool BuildProfileDataFromVendors();
@@ -142,6 +143,10 @@ private:
 
     //First Load
     bool bFirstComplete{false};
+    // The loading page gets userguide_profile_load_finish once both are true;
+    // every instance of it reports in, so the flag is never reset.
+    bool m_profile_ready{false};
+    bool m_page_ready{false};
     // Set once in the destructor. Read through `this` by the loading thread
     // (joined before `this` dies) and captured as the shared_ptr by CallAfter
     // lambdas so they don't touch `this` after the object is freed.