Run on the Namespace Mac with a fresh simulator development build. Use the PID returned by xcrun simctl launch <your-task-simulator-UDID> sh.paseo.debug. Attach only to your task's app, while no device replay is running:

PASEO_NATIVE_TEXT_REFLOW_PID=12345 \
PASEO_NATIVE_TEXT_REFLOW_LOG=/Volumes/devbox/workspace/native-text-reflow.log \
bash packages/app/e2e/mobile/native-text-reflow/ios.sh

The probe constructs the installed RNUITextView, fills its real UIKit text view, and resizes its content container from 500 to 240 and back to 500 points. It asserts the inner frame follows both widths and the same selection survives. It then recycles the view the way Fabric's pool does and remounts it 30 points wider and at the same size; the inner frame must still match the container. A zeroed frame on recycle comes back 30 or 0 points wide. This assertion checks the intermediate recycled geometry; it does not reproduce visible clipping in a mounted Fabric paragraph or exercise the subsequent drawRect call. It uses public UIView/UITextView operations, without mocking React Native. LLDB detaches after the probe. An assertion failure or evaluation error fails the shell command; the log distinguishes them.

This covers native container resizing and selection retention. It does not cover Fabric event delivery, chat row height, reader anchoring, or the on-screen copy menu. Those require the real chat journey: read an older multiline response, open/close Explorer, resize/rotate, inspect complete paragraphs and bullets, retain expanded/collapsed details, and check a stationary reader's position. Accessibility exposes full text even when glyphs are clipped, so a text wait alone does not verify that journey.