The Topic Preview shows the currently selected topic rendered as if it would have been exported. In this view you can verify that your source comments and topic files have been parsed correctly and the output will be formatted properly.
Note: The actually generated output might be completely different from how a topic looks like in the preview. This is because the output depends on the used output format and the options used when exporting it.
To copy the Topic ID to the clipboard
Right-click anywhere in the Topic Preview.
Select Copy topic ID to clipboard.
Notes
The preview of a topic is only available if the topic is exported.