An action block that get the clipboard content.
If the proceed option is set to Immediately,
then the current clipboard content is retrieved without pausing the fiber.
If set to When changed, then the fiber will pause until the clipboard content has changed.
If the clipboard contains multiple items, only the first item is assigned to content variable.
null is assigned if the content can’t be converted to text.
- Proceed — when the fiber should proceed.
- Text content — variable to assign the clipboard content.