Logging messages in personal Facebook Messenger chat to file

Hi, I'm a first time Web Scraper trying to get what seems like a simple task implemented. I would like to log messages sent to a Facebook chat conversation to a file as they come in. I am logged into a personal Facebook account, and the chat URL is of the form Redirecting...

I have a selector of "div[aria-label^=Messages]" of type SelectorElement, Multiple set to "yes", Parent selectors set to "_root". This seems to select the entire conversation panel, including several of the most recent messages of the chat.

What I would like to have happen is when the text in this area updates with a new chat message, the contents of just the new message get appended to a text file (preferably with a time stamp).

I haven't been able to figure out (a) how to detect the new message appearing, or (b) how to grab just the newly appearing text to save to file. Clicking "Data Preview" gets all of the text in the conversation panel, which if saved to the file on every new message would create a lot of redundant text and make it hard to follow.

I'm aware that Facebook has a data export option that would do this, but I am interested in getting Web Scraper to do it in near real time.

Any tips would be appreciated.


Does anyone have any pointers for scraping from personal Facebook Messenger pages?