Why don't emails have a unique ID in the subject line?

Question

Thinking about this earlier this morning as I swim through my inbox. I feel like it'd be easier to track down an email if there was a unique ID attached in the subject line. Had a co-worker ask me: "did you see that email so and so sent the other day?"Of course I did, but I also have 10-15 emails from that same person on that same day. I feel like it'd be easier to track down if someone asked "Did you see email E2YKW3 that Michelle sent the other day asking for follow up?"Perhaps a shower thought, but wanted to get the community's take on this.

bloak · Accepted Answer

There's the Message-ID field, but do e-mail clients (apart from Mutt) let you search for the message with a given Message-ID?

wtmt · Answer

How would you remember a random string if you cannot remember a subject line (or even body text) worded by a human? All email clients allow you to search the subject, body, presence/absence of attachments, from, to, etc. Message-ID, References, In-Reply-To...there are already several headers created and managed (though in a hidden way) by email clients. But the values of these headers are usually long strings that humans cannot easily remember.Open up an emails from different email threads (preferably one that has been sent later in the reply chain) and see the raw headers. There's a lot of information there. Something in it could be useful to you or for you to devise something better than the status quo.

hvass · Answer

I use email all the time and have never even remotely encountered a point where I would need something like this. Why wouldn't you simply refer to a subject line? And why would someone say "Did you see email E2YKW3" I can't imagine a single person saying that frankly.

stephenr · Answer

This is what the subject line is for. If you don&rsquo;t read the existing subject line they write, which distinguishes the various messages from a single person, and gives some indication of the topic, why would you remember some random string of characters that is otherwise meaningless?

NetOpWibby · Answer

That's an interesting thought. I'm working on a desktop IMAP client in my spare time so my burgeoning IMAP knowledge is...getting there.Would this ID be prominent? Appear on hover?

Why don't emails have a unique ID in the subject line?

There's the Message-ID field, but do e-mail clients (apart from Mutt) let you search for the message with a given Message-ID?

I use email all the time and have never even remotely encountered a point where I would need something like this. Why wouldn't you simply refer to a subject line? And why would someone say "Did you see email E2YKW3" I can't imagine a single person saying that frankly.

This is what the subject line is for. If you don’t read the existing subject line they write, which distinguishes the various messages from a single person, and gives some indication of the topic, why would you remember some random string of characters that is otherwise meaningless?

That's an interesting thought. I'm working on a desktop IMAP client in my spare time so my burgeoning IMAP knowledge is...getting there.
Would this ID be prominent? Appear on hover?