Remote Control: SendUserFile images render as blank, inert cards in iOS app and claude.ai web (display:"render" set; gap left by #67869 fix)

Summary

SendUserFile image attachments sent from a local session driven via Remote Control render as blank, inert file cards in both the Claude iOS app and claude.ai desktop web — filename and size show correctly, but there is no inline preview (grey placeholder on iOS) and tapping/clicking the card does nothing. display: "render" was set explicitly.

This appears to be the gap left by the #67869 fix: that issue described the identical symptom and was closed 2026-06-24 ("Fixed in the next release!"), but the fix was verified on the Desktop app rendering a local session. The remote-client path — iOS app / desktop web driving a Remote Control session on a separate host — still reproduces today.

Environment

• CLI: 2.1.231 (Homebrew), host: Mac mini, macOS 26.6.1 (arm64), session started from the desktop app with Remote Control connected
• Clients: Claude iOS app (current as of 2026-08-13) and claude.ai/code desktop web — both show the same behavior
• Files: PNG 472–660 KB, JPEG 64–140 KB, PNG 2.3 MB — all identical result (so not size- or format-specific)

Steps to reproduce

1. Run a local Claude Code session on machine A with Remote Control connected.
2. Drive the session from the Claude iOS app or claude.ai/code on another device.
3. Have the session call SendUserFile with a PNG and display: "render" (also reproduces with display unset).

Expected

Inline image preview — display: "render" is documented as "opens the file inline in the client".

Actual

A file card with correct type badge, filename, and size (metadata clearly reaches the client), but no thumbnail/preview and no reaction to tap/click. Reproduced across 5 different files in one session, on both clients simultaneously.

Additional signals

• In the same session, Read of the same PNG renders the image inline in the transcript, and inline SVG / visualize widgets render fine — the failure is specific to SendUserFile delivery to remote clients.
• Related open issues in the same family: #83021 (blank cards in split view), #78709 (broken thumbnails), #86337 (cards don't offer download). The Remote Control file-open path also appears broken independently: #86360, #77203 (client never sends the read_file control request).

🤖 Filed with Claude Code