Golf a Compute interpreter
05AB1E, 16 15 14 13 bytes
Code:
[Ig&gt;#w’

D€µ.

Explanation:
[        # Starts an infinite loop
 I       # Input string
  g&gt;     # Length + 1
    #    # If equal to 1, break out of the loop
     w   # Wait 1 second

This part is equivalent to &quot;\n\nDone.&quot;:
      ’  # Push &quot;\n\nDone.&quot; on top of the stack

D€µ.     # The compressed string is ended implicitly
         # Implicit, print top of the stack

Try it online!
Uses CP-1252 encoding.