Developer Tools

The webapp ships a full inspector — it is part of every cap2UI5 app, in development and in production, and nothing needs to be installed or enabled.

Open it with Ctrl+F12. You can also deep-link straight to a tab with ?z2ui5-devtools=HISTORY.

Server-driven UI moves the interesting state to the server, which makes the browser's own devtools much less useful than usual: you can see the rendered XML, but not why the server produced that XML for this click. These tools show the other half.

What is in there

The dialog has five groups.

Overview

Which app class is serving, which roundtrip you are on, and whether anything is broken. The first place to look when an app "does nothing" — usually it answers the question before you open anything else.

Problems

The Error view and the Log. Open on Error makes the dialog pop up by itself the moment something throws, which is the difference between catching an error and finding out about it three interactions later.

Roundtrips

The heart of it, and what you cannot get anywhere else:

• History — every roundtrip of this session
• Request / Response — the exact wire payloads (S_FRONT, XX, MODEL; see HTTP Protocol)
• Actions — the frontend actions the server asked for
• two diffs — what changed between roundtrips, model and view

Record Payloads keeps the full bodies instead of summaries. Retry re-sends a roundtrip, Restart starts the app over.

View & Data

The generated view, sliced by slot and aspect, plus Pick Control — click a control in the running app and land on the piece of view XML and the bound model path that produced it. After Templating shows the view as UI5 sees it once templating has run, which is where binding problems become obvious. Apply to App pushes an edited view straight into the running app, so you can try a change without a server roundtrip.

System

The UI5 version and device info, the class registry (what ?app_start= can resolve), and ABAP Source — for apps transpiled from ABAP, the original source, with Open in ADT when you are on a system that has it.

Turning it off

There is no switch. The tools are part of the shipped webapp, and the webapp is a generated artifact mirrored from upstream abap2UI5 — patching it out locally would be overwritten by the next sync. If you must remove them, do it in the pipeline: the frontend is assembled by builder-abap2UI5-js (see Ecosystem).

Worth knowing before you try: the tools expose nothing the browser could not already read. The payloads they show are this session's own requests and responses, and the class registry lists what ?app_start= accepts anyway.