diff --git a/epdb/legacy_api.py b/epdb/legacy_api.py
index 2f984548..1bdd49ff 100644
--- a/epdb/legacy_api.py
+++ b/epdb/legacy_api.py
@@ -2159,6 +2159,7 @@ class CreateEdge(Schema):
     products: str | None = None  # Node URIs comma sep
     multistep: str | None = None
     edgeReason: str | None = None
+    probability: float | None = None
 
 
 @router.post(
@@ -2226,6 +2227,10 @@ def add_pathway_edge(request, package_uuid, pathway_uuid, e: Form[CreateEdge]):
             multi_step=multi_step,
         )
 
+        if e.probability:
+            new_e.kv["probability"] = e.probability
+            new_e.save()
+
         # Update depths as sideeffect of above operation
         pw.update_depths()
 
diff --git a/templates/objects/pathway.html b/templates/objects/pathway.html
index 20102597..199c84a4 100644
--- a/templates/objects/pathway.html
+++ b/templates/objects/pathway.html
@@ -227,6 +227,29 @@
                       Reaction Names
                     </a>
                   </li>
+                  <li>
+                    <a href="{% if merged %}{{ current_object.url }}{% else %}{{ current_object.url }}?merged=true{% endif %}" id="merged-toggle-button" class="cursor-pointer">
+                      <svg
+                        id="merged-icon"
+                        xmlns="http://www.w3.org/2000/svg"
+                        width="16"
+                        height="16"
+                        viewBox="0 0 24 24"
+                        fill="none"
+                        stroke="currentColor"
+                        stroke-width="2"
+                        stroke-linecap="round"
+                        stroke-linejoin="round"
+                        class="lucide lucide-eye"
+                      >
+                        <path
+                          d="M2 12s3-7 10-7 10 7 10 7-3 7-10 7-10-7-10-7Z"
+                        />
+                        <circle cx="12" cy="12" r="3" />
+                      </svg>
+                      Merged View
+                    </a>
+                  </li>
                   {% if pathway.setting.model.app_domain %}
                     <li>
                       <a id="app-domain-toggle-button" class="cursor-pointer">
@@ -560,6 +583,8 @@
     var timeseriesViewEnabled = false;
     // Predicted Property View
     var predictedPropertyViewEnabled = false;
+    // Merged View
+    var mergedViewEnabled = new URLSearchParams(window.location.search).get("merged") !== null;
 
     function goFullscreen(id) {
       var element = document.getElementById(id);
@@ -705,6 +730,23 @@
         });
       }
 
+      const mergedViewBtn = document.getElementById(
+        "merged-toggle-button",
+      );
+      if (mergedViewBtn) {
+          const icon = document.getElementById("merged-icon");
+          if (mergedViewEnabled) {
+            // Change to eye-off icon
+            icon.innerHTML =
+              '<path d="M9.88 9.88a3 3 0 1 0 4.24 4.24"/><path d="M10.73 5.08A10.43 10.43 0 0 1 12 5c7 0 10 7 10 7a13.16 13.16 0 0 1-1.67 2.68"/><path d="M6.61 6.61A13.526 13.526 0 0 0 2 12s3 7 10 7a9.74 9.74 0 0 0 5.39-1.61"/><line x1="2" x2="22" y1="2" y2="22"/>';
+          } else {
+            // Change back to eye icon
+            icon.innerHTML =
+              '<path d="M2 12s3-7 10-7 10 7 10 7-3 7-10 7-10-7-10-7Z"/><circle cx="12" cy="12" r="3"/>';
+        }
+      };
+
+
       // Timeseries toggle
       const timeseriesBtn = document.getElementById("timeseries-toggle-button");
       if (timeseriesBtn) {
diff --git a/utilities/misc.py b/utilities/misc.py
index 36b1ce7d..f429a9fd 100644
--- a/utilities/misc.py
+++ b/utilities/misc.py
@@ -214,6 +214,7 @@ class EdgeExportSchema(RefEdgeExportSchema):
     start_nodes: List[RefNodeExportSchema]
     end_nodes: List[RefNodeExportSchema]
     scenarios: List[RefScenarioExportSchema]
+    kv: Optional[dict]
 
 
 class PathwayExportSchema(RefPathwayExportSchema):
@@ -623,6 +624,7 @@ class PackageImporter:
                 new_e.description = e.description
                 new_e.aliases = e.aliases
                 new_e.edge_label = self._cache[e.edge_label.uuid]
+                new_e.kv = e.kv
                 new_e.save()
 
                 for sn in e.start_nodes: