What would be a good universal icon for
attest / endorse / recommend / second that?

Here are some thought starters.

icebreaker

this is a great question

i’ve been use a hex check on /icebreaker 

i like 7 & 19 of your options here

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co-founder at icebreaker.xyz/j4ck.fc • /icebreaker • /swagcaster • /bromero • /design

You found a good one in #19.

'Attest' is stronger than 'like', but there's a heart shape in the design that gives a nod to 'like'.

The intersection shows the interconnectivity that the attestations create onchain.

The diamond shape is a nod to Ethereum.

The overall shape is like a badge.

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