In 2021, ICAO (the International Civil Aviation Organization, which standardises passports) released an updated standard, introducing LDS2 (Logical Data Structure 2). This is a new section of the passport chip that allows the storage of further data, including travel history, visa records, and additional biometric data. LDS2 completely changes what a passport is. Current passports are read-only, but with LDS2, they become writable. Passport stamps and visas become digital. Passports go from being an identification document to a detailed record of your movements. Source
2017 findings on E-Passport validation: A practical
experience
2016 Germany Advanced Security Mechanisms for Machine
Readable Travel Documents and eIDAS Token
https://core.ac.uk/download/pdf/132743224.pdf
More complete list of possible sig algs from jmrtd here.
730M e-passports total: https://www.nxp.com/docs/en/white-paper/the-future-of-epassports-and-border-crossings-whitepaper.pdf