Plugin changes html code on update

Uploaded plugin as wanted to prevent stripping out of structured data on switching between visual and text.

At first looked great but on saving it alters all the html code
Example

‘<div itemscope itemtype=”https://schema.org/CreativeWork”>&#8217;
to

<div itemscope=”” itemtype=”https://schema.org/CreativeWork”></div&gt;

I cannot get the post to show the code as is – suffice to say it changes the < and > to &lt and &gt
Any thoughts?

Thanks

https://www.ads-software.com/plugins/preserved-html-editor-markup/