diff --git a/toolkit/components/passwordmgr/LoginManagerParent.jsm b/toolkit/components/passwordmgr/LoginManagerParent.jsm
index 418ab6dcfc2a..9fa46e573da9 100644
--- a/toolkit/components/passwordmgr/LoginManagerParent.jsm
+++ b/toolkit/components/passwordmgr/LoginManagerParent.jsm
@@ -107,8 +107,9 @@ var LoginManagerParent = {
       return;
     }
 
+    let allLoginsCount = Services.logins.countLogins(formOrigin, "", null);
     // If there are no logins for this site, bail out now.
-    if (!Services.logins.countLogins(formOrigin, "", null)) {
+    if (!allLoginsCount) {
       target.sendAsyncMessage("RemoteLogins:loginsFound",
                               { requestId: requestId, logins: [] });
       return;
@@ -152,6 +153,16 @@ var LoginManagerParent = {
     var logins = Services.logins.findLogins({}, formOrigin, actionOrigin, null);
     target.sendAsyncMessage("RemoteLogins:loginsFound",
                             { requestId: requestId, logins: logins });
+
+    const PWMGR_FORM_ACTION_EFFECT =  Services.telemetry.getHistogramById("PWMGR_FORM_ACTION_EFFECT");
+    if (logins.length == 0) {
+      PWMGR_FORM_ACTION_EFFECT.add(2);
+    } else if (logins.length == allLoginsCount) {
+      PWMGR_FORM_ACTION_EFFECT.add(0);
+    } else {
+      // logins.length < allLoginsCount
+      PWMGR_FORM_ACTION_EFFECT.add(1);
+    }
   },
 
   doAutocompleteSearch: function({ formOrigin, actionOrigin,
diff --git a/toolkit/components/telemetry/Histograms.json b/toolkit/components/telemetry/Histograms.json
index cf171cb1bc5e..fa39248b15f1 100644
--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -7360,6 +7360,12 @@
     "extended_statistics_ok": true,
     "description": "The number of sites for which the user has explicitly rejected saving logins"
   },
+  "PWMGR_FORM_ACTION_EFFECT": {
+    "expires_in_version": "never",
+    "kind": "enumerated",
+    "n_values" : 5,
+    "description": "The effect of the form action on signon autofill. (0=No effect, 1=Fewer logins after considering the form action, 2=No logins match form origin and action."
+  },
   "PWMGR_FORM_AUTOFILL_RESULT": {
     "expires_in_version": "never",
     "kind": "enumerated",