Recipe:
Draw two linked text frames on a document page.
Type some text into the first frame.
With the first frame still selected, Layer > Convert to Curves.
Result:
The first frame and its contents are converted to group and the text within is converted to curves, as expected.
The text is also duplicated into the linked frame.
Before step 3 of the recipe:
After step 3:
convert-to-curves.afpub