Appium iOS Safari loads local Slate routes but XCUITest value does not drive contenteditable

What happened

The current agent-browser iOS provider became unreliable on local Next dev example routes:

• routes opened
• but the page often exposed only the Next shell
• #placeholder-ime never appeared

Direct Appium + XCUITest Safari was a better transport for setup truth:

• it loads /examples/placeholder?debug=1
• it loads /examples/placeholder-no-feff?debug=1
• it can read the real editor HTML and body text from those routes

So Appium iOS is a better setup transport than the current agent-browser iOS path here.

What still failed

Typing through the standard WebDriver element value path is still red on iOS Safari contenteditable surfaces.

Observed shape:

• repeated input:undefined:[null]
• blockTexts stays empty
• slateSelection stays 0.0:0|0.0:0

That happened on both:

• FEFF placeholder
• no-FEFF placeholder

Additional follow-up probes did not unlock a better primitive:

• W3C key actions against the focused Safari page had no effect
• Appium XCUITest mobile: keys / /wda/keys against the focused Safari page also had no effect
• switching to NATIVE_APP after focus showed a real native context, but no XCUIElementTypeKeyboard or XCUIElementTypeKey nodes appeared
• even a native coordinate tap translated from the web element rect through mobile: calibrateWebToRealCoordinatesTranslation still did not surface the iOS keyboard

Why this matters

This cleanly separates two iOS problems:

1. agent-browser iOS route/render reliability
2. Appium/XCUITest contenteditable input semantics

They are not the same failure.

Upstream follow-up:

• appium/appium-xcuitest-driver#2803

Reusable rule

For local iOS Safari proof on this repo:

• use direct Appium iOS when you need trustworthy route/setup truth
• do not treat XCUITest element/value as trustworthy contenteditable typing proof
• do not assume native-context tapping will surface an iPhone keyboard here just because NATIVE_APP exists; verify the keyboard tree first
• if Appium setup is green but typing is red, record the lane as setup-green / behavior-red