Upload your friends list HTML file to analyze the names.
How to Download Your Facebook Friend Data
Navigate to Settings & Privacy within Facebook using a web browser such as Chrome, Safari, or Edge (the app no longer allows data downloads).
Go to settings and find Download your Information under Your Information.
Click Continue.
Click Download your information.
Select the profile from which you want to download your friend's list or select multiple!
Then click Specific types of information. If you only want to download your friend's list, feel free to do so. It is recommended to download all the data, as it is interesting, but this will take longer.
If selecting Specific types of information, scroll down and choose Friends if pulling from Facebook or Followers and Following if pulling data from Instagram.
Select Download to Device and click next.
Update the Date Range to All Time. Make sure the format is in HTML and the right email is selected to receive the file. Upon entering those fields, click Create Files. Facebook will take 1-4 days (usually shorter) to process your request and provide the data as a ZIP file to your email.
Once you have the ZIP file, decompress it by extracting its contents. Inside the extracted folders, navigate to Connections -> Friends for Facebook data, or Connections -> Followers if using Instagram data. The file you'll need to load for analysis will be named your_friends.html or your_followers.html, depending on the source of your data.