Two gaps, one in each direction.
Android could ENCODE an address and had no way to DERIVE one, so it
could not show yours and nobody on another relay could be given it --
the cross-relay work was iOS-only in practice. The engine was missing
`localAccountSalt` and a way to get both sign-in secrets from one
stretch; asking for the account key separately re-runs 650,000 PBKDF2
iterations for a value already in hand. The salt is pinned against the
JavaScript engine, which is normative -- a Kotlin test asserting what
Kotlin computes would prove only that Kotlin is self-consistent, and
the failure to guard against is three engines disagreeing, which shows
up as one person having two addresses depending on which phone they
used.
The address is stored in the vault because it can only be derived at
sign-in: the passphrase exists for that one moment and is never kept,
so a restored session had nothing to recompute from. Caught by the
empty state saying so on the emulator rather than showing a blank.
A QR encoder, written rather than depended on. Android has no encoder
in the platform, and this is one fully specified algorithm for one
fixed job -- turning a short ASCII address into a bitmap. It is
verified by DECODING: thirteen codes, every version from 1 to 10 at
exact capacity, read back by CoreImage's detector, which shares no line
with it. That found the bug that mattered. The symbol was structurally
perfect -- finders, timing, alignment, data placement and mask all
confirmed correct against a reference symbol -- and nothing could read
it, because the fifteen format bits were written least-significant
first. It fails identically at every version with no clue where.
The Account screen was a flat stack of fields, buttons and paragraphs
with dividers between them, so a security setting carried the same
weight as a text box and "Delete account" the same as "Save display
name". Cards now, matching the Contacts screen that already had them,
with the destructive pair on their own.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
