How to show more passage text after selecting large window?

Twine Version: 2.3.10 | Story Format: Harlowe 3.2.0

I changed the passage window size to large, yet instead of showing more text, it just shows white space.

Here is an image of the problem:

The simple answer is you can’t.

The Twine 2.x application code that extracts the ‘excerpt’ from the Passage content, to be displayed within the Story Map widget, has a fixed limit of 99 characters. You would need to alter the application’s source code to make it extract more content.