Prevent crashing when removing the last plugin in the list

Author: moooorg

qt/OpenRGBPluginsPage/OpenRGBPluginsPage.cpp

@@ -350,6 +350,15 @@ void Ui::OpenRGBPluginsPage::on_PluginsList_itemSelectionChanged()
     \*-----------------------------------------------------*/
     int cur_row = ui->PluginsList->currentRow();
 
+    /*-----------------------------------------------------*\
+    | Disable the remove button if no item selected         |
+    \*-----------------------------------------------------*/
+    if(cur_row == -1)
+    {
+        ui->RemovePluginButton->setEnabled(false);
+        return;
+    }
+
     /*-----------------------------------------------------*\
     | Enable the remove button when there's a selected item |
     | and the selected item is not a system plugin          |