I ran a couple of prompts to reverse-engineer my ~/Library/Application Support/Firefox/Profiles/*/sessionstore-backups/recovery.jsonlz4" file - Codex figured out how to lz4 decompress the file, then I had it interpret some base64 encoded binary data in the JSON, that session is here: https://gisthost.github.io/?986cb066dd8502cf0200a5cc6fdeb4c6