We have further investigated the issue.
It seems that some other plugin is adding some code in the Span tag code and hence it is causing the issue.
1] For the URL –
https://www.superiorscaffold.com/inside-out-at-the-kaiserman-jewish-community-center-in-wynnewood-pa/
The Span tag code is –
<span st_title='Inside Out at the Kaiserman Jewish Community Center in Wynnewood, PA' st_url='https://<a href="https://www.superiorscaffold.com/inside-out-at-the-kaiserman-jewish-community-center-in-wynnewood-pa" target="_blank">www.superiorscaffold.com/inside-out-at-the-kaiserman-jewish-community-center-in-wynnewood-pa</a>/' class='st_plusone'></span>
The “st_url” contains a ‘href’ and hence it is causing the issue.
2] For the URL –
https://www.superiorscaffold.com/blog/
You can check the Span tag code –
<span st_title='Penn Presbyterian Medical Center – New 178,000 square foot advanced care pavilion' st_url='https://www.superiorscaffold.com/penn-presbyterian-medical-center-new-178000-square-foot-advanced-care-pavilion/' class='st_plusone'></span>
It is clear and doesn’t contain any extra character.
We suggest you to check your installed plugins, whether they are conflicting (and inserting the contents) with ShareThis Plugin or not.
Also, you can change the “st_url” content from the ShareThis Plugin Settings Menu – Step6 under “View & edit code:”
Screenshot – https://screencast.com/t/NnTYCIZ8QY
Hope this helps.