@agsteele- good point. I'll highlight the issue.
This is a screenshot of my phone, running Instapaper, viewing a saved article.
I have now added a highlight and comment on a text block - which contains a URL.
When the highlighted text block is sent to Evernote, the URL link has been stripped from the text.
I've tried 2 methods of syncing highlighted text from Instapaper to Evernote - both do not retain the URL in the text:
1. Built-in Instapaper to Evernote Integration (this is configured on Instapaper)
2. Using IFTTT to copy any new Instapaper highlights to Evernote.
It could well be that this is an Instapaper issue - I've emailed them.