Notice: Undefined variable

I’m getting this notice when I’m trying to use the shortcode on pages:

Notice: Undefined variable: out in /—/—/—/—/wp-content/plugins/animated-headline/settings.php on line 103

(I’ve replaced website path details with dashes)

I can see someone else had the problem a while back but it’s marked as resolved, but shows no steps or comments to resolve it. Can you please help?

Thank you.

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