[Bug] Desktop v0.4.26 renders completely blank on macOS 12.7.6 arm64

[marketreadyai]

Summary

The official Buzz Desktop v0.4.26 application opens as a completely
blank full-size window on macOS 12.7.6 (Apple Silicon).

The native application starts, but the frontend never commits its
initial render.

Environment

• macOS: 12.7.6
• Build: 21H1320
• Architecture: arm64
• Safari: 17.6
• Buzz: 0.4.26
• Bundle ID: xyz.block.buzz.app
• Executable architecture: arm64
• Installation: official notarised DMG
• Gatekeeper: accepted
• Code signature: valid
• Declared minimum macOS version: 10.15

Steps to reproduce

1. Install the official Buzz Desktop v0.4.26 arm64 DMG.
2. Open Buzz.
3. Observe that the entire application window is blank.

I also reproduced it after:

• quitting Buzz;
• confirming nothing was listening on port 3000;
• backing up/removing Application Support, WebKit, cache, preferences and
  saved-window state;
• relaunching Buzz with clean first-run state.

Expected result

Buzz displays its welcome/onboarding interface.

Actual result

The entire application window is blank. There are no visible controls,
messages or onboarding UI.

Native startup output

buzz-mesh: installed tokio runtime with 8 MiB worker stacks
buzz-desktop: persisted identity pubkey [public key omitted]
buzz-desktop: repos dir resolved at boot — no configured override, REPOS is the default real dir
buzz-desktop: media proxy listening on 127.0.0.1:[dynamic port]
buzz-desktop: initial render did not commit before reveal timeout

Additional diagnostic information

• The native Buzz process remains running.
• com.apple.WebKit.WebContent starts.
• No application-level JavaScript exception appears in macOS unified logs.
• The issue persists with port 3000 free.
• On the first launch, another local Node application occupied port 3000,
  which caused a separate "relay returned an unexpected HTML page" message.
  Removing that conflict did not fix the blank renderer.
• Docker is unavailable on this Mac, but this report concerns the packaged
  desktop application's onboarding renderer, before any self-hosted relay
  setup.

I can provide the filtered macOS WebKit log and a screenshot of the completely
blank window if useful.