diff --git a/sdrbase/maincore.cpp b/sdrbase/maincore.cpp
index 7d6b842d9..dd46fef00 100644
--- a/sdrbase/maincore.cpp
+++ b/sdrbase/maincore.cpp
@@ -39,6 +39,8 @@ MESSAGE_CLASS_DEFINITION(MainCore::MsgSaveFeatureSetPreset, Message)
 MESSAGE_CLASS_DEFINITION(MainCore::MsgDeleteFeatureSetPreset, Message)
 MESSAGE_CLASS_DEFINITION(MainCore::MsgAddDeviceSet, Message)
 MESSAGE_CLASS_DEFINITION(MainCore::MsgRemoveLastDeviceSet, Message)
+MESSAGE_CLASS_DEFINITION(MainCore::MsgAddFeatureSet, Message)
+MESSAGE_CLASS_DEFINITION(MainCore::MsgRemoveLastFeatureSet, Message)
 MESSAGE_CLASS_DEFINITION(MainCore::MsgSetDevice, Message)
 MESSAGE_CLASS_DEFINITION(MainCore::MsgAddChannel, Message)
 MESSAGE_CLASS_DEFINITION(MainCore::MsgDeleteChannel, Message)
diff --git a/sdrbase/maincore.h b/sdrbase/maincore.h
index 5eb665d2c..f12fc3063 100644
--- a/sdrbase/maincore.h
+++ b/sdrbase/maincore.h
@@ -250,8 +250,7 @@ public:
     public:
         int getDirection() const { return m_direction; }
 
-        static MsgAddDeviceSet* create(int direction)
-        {
+        static MsgAddDeviceSet* create(int direction) {
             return new MsgAddDeviceSet(direction);
         }
 
@@ -268,8 +267,7 @@ public:
         MESSAGE_CLASS_DECLARATION
 
     public:
-        static MsgRemoveLastDeviceSet* create()
-        {
+        static MsgRemoveLastDeviceSet* create() {
             return new MsgRemoveLastDeviceSet();
         }
 
@@ -279,6 +277,34 @@ public:
         { }
     };
 
+    class SDRBASE_API MsgAddFeatureSet : public Message {
+        MESSAGE_CLASS_DECLARATION
+
+    public:
+        static MsgAddFeatureSet* create() {
+            return new MsgAddFeatureSet();
+        }
+
+    private:
+        MsgAddFeatureSet() :
+            Message()
+        { }
+    };
+
+    class SDRBASE_API MsgRemoveLastFeatureSet : public Message {
+        MESSAGE_CLASS_DECLARATION
+
+    public:
+        static MsgRemoveLastFeatureSet* create() {
+            return new MsgRemoveLastFeatureSet();
+        }
+
+    private:
+        MsgRemoveLastFeatureSet() :
+            Message()
+        { }
+    };
+
     class SDRBASE_API MsgSetDevice : public Message {
         MESSAGE_CLASS_DECLARATION
 
diff --git a/sdrbase/webapi/webapiadapter.cpp b/sdrbase/webapi/webapiadapter.cpp
index 25bda5cbc..30278defa 100644
--- a/sdrbase/webapi/webapiadapter.cpp
+++ b/sdrbase/webapi/webapiadapter.cpp
@@ -1408,7 +1408,11 @@ int WebAPIAdapter::instanceDeviceSetDelete(
         SWGSDRangel::SWGSuccessResponse& response,
         SWGSDRangel::SWGErrorResponse& error)
 {
+#ifdef SERVER_MODE
+    if (m_mainCore->m_deviceSets.size() != 0)
+#else
     if (m_mainCore->m_deviceSets.size() > 1)
+#endif
     {
         MainCore::MsgRemoveLastDeviceSet *msg = MainCore::MsgRemoveLastDeviceSet::create();
         m_mainCore->m_mainMessageQueue->push(msg);
@@ -1431,22 +1435,41 @@ int WebAPIAdapter::instanceFeatureSetPost(
         SWGSDRangel::SWGSuccessResponse& response,
         SWGSDRangel::SWGErrorResponse& error)
 {
-    (void) response;
-    error.init();
-    *error.getMessage() = "Not implemented";
+    (void) error;
+    MainCore::MsgAddFeatureSet *msg = MainCore::MsgAddFeatureSet::create();
+    m_mainCore->m_mainMessageQueue->push(msg);
 
-    return 501;
+    response.init();
+    *response.getMessage() = QString("Message to add a new feature set (MsgAddFeatureSet) was submitted successfully");
+
+    return 202;
 }
 
 int WebAPIAdapter::instanceFeatureSetDelete(
         SWGSDRangel::SWGSuccessResponse& response,
         SWGSDRangel::SWGErrorResponse& error)
 {
-    (void) response;
-    error.init();
-    *error.getMessage() = "Not implemented";
+#ifdef SERVER_MODE
+    if (m_mainCore->m_featureSets.size() != 0)
+#else
+    if (m_mainCore->m_featureSets.size() > 1)
+#endif
+    {
+        MainCore::MsgRemoveLastFeatureSet *msg = MainCore::MsgRemoveLastFeatureSet::create();
+        m_mainCore->m_mainMessageQueue->push(msg);
 
-    return 501;
+        response.init();
+        *response.getMessage() = QString("Message to remove last feature set (MsgRemoveLastFeatureSet) was submitted successfully");
+
+        return 202;
+    }
+    else
+    {
+        error.init();
+        *error.getMessage() = "No more feature sets to be removed";
+
+        return 404;
+    }
 }
 
 int WebAPIAdapter::devicesetGet(