He is asking Perplexity to summarize a single page. This is simply automation for opening a browser, navigating to that URL, copying the content, pasteing the content into Perplexity.
This is not automated crawling or indexing. Since the person is driving the action. An automated crawler is driven into action by a bot.
Nor is this article added into the foundational model. It's simply in a person's session context.
If for some reason, the community deems this as automated crawling or indexing. One could write an extension to automate the process of copying the article content & pasting the content into an LLM/Rag like Perplexity.