feeRecipient and coinbase in Eth2

[upavloff]

As I understand there will not be a coinbase transaction in the execution payload of blocks after the merge (eip-3675). However, looking at the specs we can see there is a fee_recipient which, according to ethereum/execution-apis#130 may be a hidden coinbase transaction.

I cannot parse this pull request, is the fee_recipient indeed, just a fee recipient and the pull request change the terms because there will not be coinbase transaction anymore or is this pull request deprecated in its explanation?