Facebook – Can someone hack the Facebook profile after I schedule it to delete permanently

No. Each message is transacted with a unique email ID. The inbox for each user is independent of messages. i.e., the message you send is not linked and stored internally with the inbox of the receiver.

Each mail transaction like draft, inbox and trash act independently with regards to the email user. Hence, manipulating any message will only reflect your email.

At least no major service provides allow such cross deletion.

Any messaging system doesn't allow you to delete item from another's inbox by deleting your own. Gmail will treat a message as a thread. So if you have a message in the inbox and also have stored it in a particular label, deletion of that message from the inbox leads to deletion from label.

However, it does not remove from your friend's Facebook inbox, it's that simple.

1. No. It's integrated to Facebook search algorithm. Public don't have access to it.

   This has been made possible recently (near the end of 2012). Here's how you can delete your search history:

   • Go to your profile and click on "Activity Log".

   

   • On the left sidebar, you will see options like Photos etc.

   

   • Expand them if needed by clicking on "MORE" until you find one that says "Search". Click on it.

   

   • You will see all your Search history. Click on the link that says "Clear History" on top of it.

   

   • Click "Clear Searches" on the confirmation box that appears as the last step.

   

2. No. That's not public. Some apps claim to show you who visited your profile. But they are just scam. It's not possible. Facebook doesn't provide such information.