The Copy Text item is available via the Insert and Extract Text button on the collection toolbar, except when the Recycle Bin tab is active.
Select the Copy Text item to place the selected part of the text of the active clip onto the Windows clipboard. You can also copy text by pressing Ctrl+C on the keyboard while editing the clip's text. If you want to copy the entire clip, use the Copy to Clipboard button instead.
See Editing Clips and Text to learn how to use AceText.