user124148: I've been researching into Overt (Version rolling) ASICBoost and tracking some of the latest mined blocks on https://asicboost.dance.
I've noticed that all recently mined blocks have the version ending in 4 i.e. by setting bit 2. I know that miners are signalling support for Segwit by setting bit 1. So, I'm not sure what they're signalling by setting bit 2?
I have been through many of the BIP documentations, but cannot seem to find any references for bit 2 being set. I've also reviewed a similar question already asked but the answer does not focus on bit 2. Some miners set the nVersion field of the block header to 0x8000004. What were they signalling for? Was this an error?

user48884: They are signaling for Taproot. BIP 341 specifies that signaling occurs on bit 2.

124148: <p>I've been researching into Overt (Version rolling) ASICBoost and tracking some of the latest mined blocks on <a href="https://asicboost.dance" rel="noreferrer">https://asicboost.dance</a>.</p>
<p>I've noticed that all recently mined blocks have the version ending in 4 i.e. by setting bit 2. I know that miners are signalling support for Segwit by setting bit 1. So, I'm not sure what they're signalling by setting bit 2?</p>
<p>I have been through many of the BIP documentations, but cannot seem to find any references for bit 2 being set. I've also reviewed a similar question already asked but the answer does not focus on bit 2. <a href="https://bitcoin.stackexchange.com/questions/96561/some-miners-set-the-nversion-field-of-the-block-header-to-0x8000004-what-were-t">Some miners set the nVersion field of the block header to 0x8000004. What were they signalling for? Was this an error?</a></p>
 48884: <p>They are signaling for Taproot. BIP 341 <a href="https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki#Deployment" rel="noreferrer">specifies</a> that signaling occurs on bit 2.</p>
