Facebook friends / people search backup in web browser

facebook_friends_people_search_backup.js

/* Facebook friends / people search backup in web browser
 * Scroll down to your friends page or a people search page to load all profiles
 * Copy-paste the script below in a web browser console (F12 key or Ctrl+Shift+K shortcut in a browser like Firefox) and execute the desired function
 * A textarea will appear at the end of the page so you can copy the data and paste it in a text file before saving it as a CSV file
 * You can then view your backup in a spreadsheet editor like LibreOffice Calc
 * You can also compare the backup with another one to see who removed you from their friends list or who appeared in a new search (e.g. with the Linux diff command)
 * If the friend changed their name or profile URL, you can still find them with their profile ID which is backed up in the last column (open facebook.com/PROFILE_ID in a web browser)
 * The Facebook Graph API was not used because they are locking or deprecating most of their endpoints (e.g. https://developers.facebook.com/docs/graph-api/changelog/breaking-changes/#taggable-friends-4-4)
 */

var data = [];

function FacebookFriendsBackup()
{
	var list = document.getElementsByClassName("uiProfileBlockContent");
	var length = list.length;

	// note: firstChild is a bit faster than firstElementChild: https://jsperf.com/firstelementchild-and-firstchild
	for (var i = 0; i < length; ++i) {
		var link = list[i].getElementsByTagName("a")[0];
		data[i] = link.firstChild.nodeValue;
		data[i] += "\t" + link.href;
		var json = JSON.parse(link.getAttribute("data-gt"));
		if (json) { // JSON data is null when the Facebook profile is deactivated
			data[i] += "\t" + json.engagement.eng_tid; // get profile ID in case the Facebook user changes their profile URL
		}
	}
	
	displayData();
}

// can be used to backup a people search (for example to see when someone from another country or city moves to a new city)
function FacebookPeopleSearchBackup()
{
	//var list = document.getElementById("browse_result_area").getElementsByClassName("FriendRequestOutgoing"); // missing results since friend button is disabled on some profiles
	var list = document.querySelectorAll('#BrowseResultsContainer > div, [data-testid="results"] > div');
	var length = list.length;
	
	for (var i = 0; i < length; ++i) {
		data[i] = JSON.parse(list[i].firstChild.getAttribute("data-bt")).id;
		
		// comment previous line and uncomment following lines if you want full name and profile URL also
		/*var link = list[i].getElementsByTagName("a")[1];
		data[i] = link.title;
		data[i] += "\t" + link.href;
		data[i] += "\t" + JSON.parse(list[i].firstChild.getAttribute("data-bt")).id;*/
	}
	
	displayData();
}

// can be used to backup group members with things in common (https://www.facebook.com/groups/XXX/members_with_things_in_common/)
function FacebookPeopleCommonBackup()
{
	var list = document.querySelectorAll("[id^=things_in_common_]");
	var length = list.length;
	
	for (var i = 0; i < length; ++i) {
		data[i] = list[i].id.substr(17);
		
		// comment previous line and uncomment following lines if you want full name and profile URL also
		/*var link = list[i].getElementsByTagName("a")[1];
		data[i] = link.title;
		data[i] += "\t" + link.href;
		data[i] += "\t" + list[i].id.substr(17);*/
	}
	
	displayData();
}

function displayData()
{
	var box = document.createElement("textarea");
	box.value = data.join('\n');
	document.body.appendChild(box);
}

What is a web browser console?

@hoshi411 it is a web browser area where you can execute custom JavaScript code, you can open it with the F12 key or Ctrl+Shift+K shortcut in a browser like Firefox (I just updated the script comment to mention this for people who are not familiar with it).