Unit Test microflow Show Page activity not working

We are trying to test URL validity using URL Redirect widget on a page.  Unit test microflow constructs this URL dynamically and opens the page using Open Page activity. But the open page activity is not working in unit test microflow and same works fine if I run the microflow from Navigation menu. Below is my microflow and the page     Any idea on fixing this issue? or if there is any other way to check whether the URL is valid or not?
1 answers

Creating a widget that does the URL validation via java. Like this example: https://www.tutorialspoint.com/how-to-check-if-an-url-is-valid-or-not-using-java.