To Find Your First Facebook Messages With Someone
1. Go to mobile.facebook.com/messa
2. Right click on “See Older Messages…” and copy the link.
3. The link you copied will include something like this: &last_message_timestamp=1234567890123 — Completely remove this from the URL. If you don’t, the next stop won’t work.
4. In the URL, you should also see start=7 (or some other number). This specifies to show messages starting with your 7th most recent message. Change this number to the number of total messages you have with that person.
To find this number, go to facebook.com/messages on the main desktop site and then select the person. As you scroll up through the message history, you should find the total message count in parentheses:
So simply change the value in the URL to start=17140.
You may have to click “See Older Messages…” once or twice if the number was a little bit off.
To Find Facebook Messages With Someone On A Specific Date
1. Go to mobile.facebook.com/messa
2. Right click on “See Older Messages…” and copy the link.
3. The link you copied will include something like this: &last_message_timestamp=1234567890123 — This number is the Unix timestamp (with milliseconds) that the chat history begins with. Simply change this number to the desired timestamp.