Transaction – What is this OP_RETURN value?

I was messing around with blockchain learning about the equivalent use of OP_RETURN output and input data on Ethereum and I came across something interesting, but I don’t understand it.

It starts with an ETH transaction.

0xd304e780755f46e62a42884421e39af06342f0a4989704ee02989043769c4f93

Once decoded, a Bitcoin address is mentioned in the input data.

bc1q0rggj4h837qcldhv8hwxpva32nf645excexqq2

Looking at this Bitcoin address, I found that there was a transaction like this:

444a6542a01d6ce10c9fe01e323447fcf73047b78d8de10a05fa14243233a3a2

Based on the timing and value of the ETH and BTC transactions, I assumed this was some kind of coin exchange (I was exchanging ETH for BTC). I had never thought of using OP_RETURN in this way, so I thought it was pretty cool. However, I noticed that the Bitcoin transaction above has another OP_RETURN output, which is decoded as follows:

OUT:D304E780755F46E62A42884421E39AF06342F0A4989704EE02989043769C4F93 <-- There is a space at the end

At first I thought it might be a Doge coin address starting with “D”, but it was so long that I was now more curious. Does anyone know what that D304 is?