Undefined index: #attributes in ParagraphsFeatures.php with Claro

Problem/Motivation

When adding the first paragraph, the attributes array of the placeholder add element has not attributes

Steps to reproduce

Install Claro and set it as backend theme. Open "Add Node Page" and add a paragraph. After switching between paragraph following error message appears in network tab:

<br />
<b>Notice</b>:  Undefined index: #attributes in <b>/app/thunder/docroot/modules/contrib/paragraphs_features/src/ParagraphsFeatures.php</b> on line <b>96</b><br />
<br />
<b>Notice</b>:  Trying to access array offset on value of type null in <b>/app/thunder/docroot/modules/contrib/paragraphs_features/src/ParagraphsFeatures.php</b> on line <b>96</b><br />

Proposed resolution

Check if attributes array exists and only add ScrollToElementCommand if the attributes array exists.