https://groups.google.com/g/bitcoindev/c/CbfbEGozG7c/m/w2B-RRdUCQAJ
Certain flaws in the WabiSabi protocol made it possible for a dishonest coordinator to tie inputs and outputs across Tor sessions by using different cryptographic parameters for anonymous credentials per user.
https://rubin.io/public/pdfs/unfedcovenants.pdf
A new style of covenant that does not require a soft fork in which users trust oracles to be responsive but rely on enconomic incentives for the oracles to be honest.