there is no "extranonce" in a coinbase input..
You know that Google is free to use, right?
https://bitcoin.stackexchange.com/questions/5048/what-is-the-extranonce...extraNonce gets put into the input of the generation transaction...
https://en.bitcoin.it/wiki/Block_hashing_algorithm... extraNonce field which is part of the coinbase transaction...
https://aantonop.com/glossary-archive/bitcoin-extra_nonce/As difficulty increased, miners often cycled through all 4 billion values of the nonce without finding a block. Because the coinbase script can store between 2 and 100 bytes of data, miners started using that space as extra nonce space, allowing them to explore a much larger range of block header values to find valid blocks.
https://www.freecodecamp.org/news/how-bitcoin-mining-really-works-38563ec38c87/...The solution to this is to add a field to the coinbase (the transaction contents of a block, stored as the merkle tree) called the extraNonce...
what you mean is probably what you quoted me saying. where the output is not a valid address/signature but a space re utilised to form a message
Nope. That is another possibility though. You can use something like OP_RETURN in the output script making the output unspendable, and then you can put arbitrary data into that output script. That can happen with ANY transaction. You don't need to be a miner to do that.
as you can see in a coinbase transaction it needs no 'signature' because it is a reward generated coin. and so you can put anything into the signature area.. this is not a "extra nonce" this is just a script/signature area.
You've just finished trying to tell me (incorrectly) that the output is re-utilized to form a message, and then immediately afterwards you've proven my point by showing AND stating that the message is in the "signature area" (which is in the INPUT just like I stated). This script/signature area in the input IS used to store an extranonce when it is part of a generation transaction specifically because the generation transaction does not need a signature, so the space can contain anything (including a message). Generally when this area is used for a message the output IS a valid address, and is NOT re-utilized to form a message. That's because this output is how the miner (or pool) gets paid!
"extranonce" is usually deemed the utility of changing the time stamp by upto ~70 minutes(4200 permutations(12bits of timestamps 4bytes))
it is not. Changing the timestamp is changing the timestamp. It is a value that carries meaning. The nonce (and the extranonce) in a bitcoin block are arbitrary values that carry no meaning and exist solely for the purpose of calculating a different hash value from an otherwise identical source data.