fb_delete.js

// Load Facebook's mobile activity log
// https://m.facebook.com/#{you}/allactivity?log_filter=all

// loads jQuery into Facebook
var jq = document.createElement('script');
jq.src = "//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js";
document.getElementsByTagName('head')[0].appendChild(jq);

// wait for jQuery to load up.
setTimeout(removeIt, 2000);

function removeIt() {
	jQuery.noConflict();
	// This is the 'drop down' that exposes the post options of a post. Click them all.
	jQuery('[data-sigil="touchable flyout-causal"]').trigger("click");

	// Find all spans that say "delete", and click them.
	deletes = jQuery("span:contains(Delete)");
	console.log("Deleted " + deletes.length);
	jQuery("span:contains(Delete)").trigger("click");

  // Find all spans that say "unlike", and click them.
	unlikes = jQuery("span:contains(Unlike)");
	console.log("Unliked " + unlikes.length);
	unlikes.trigger("click");
console.log("purge done");
};

// You've now deleted or unliked everything in the page. Expand the days, months, and years, to delete more.