Alternative Text in a Text Box Object

I'm hitting the same problem. I want the screen reader to read the text in the text box, so I don't think alt text is needed. The text of the paragraph is too long for alt text, and specifying different alt text for a text box seems redundant and counter-productive.

I suppose the work-around is to create a lot of small text boxes with smaller character counts, so that when Storyline uses the text in the text box as redundant alt text, the text doesn't exceed the character limit. But I'm still confused about why this is happening at all.