$this->tabId
If this Plugin is part of a tabbed Plugin Nest, $this->tabId will store the Tab's id in the nested_plugins table.
If this Plugin is not part of a Nest, or the Plugin is part of a Nest but no tabs have been set up, $this->tabId will be 0.
Can be used in methods called by plugins. From Zenario 7.0.0 onwards.