Bug 245314

Summary: Web Inspector: DOM tree is missing parts of the DOM tree when remotely inspecting iOS devices
Product: WebKit Reporter: Jeff Johnson <opendarwin>
Component: Web InspectorAssignee: Patrick Angle <pangle>
Status: RESOLVED FIXED    
Severity: Normal CC: inspector-bugzilla-changes, pangle, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: Safari Technology Preview   
Hardware: iPhone / iPad   
OS: iOS 16   
Attachments:
Description Flags
Screenshot of Safari Technology Preview web inspector none

Description Jeff Johnson 2022-09-17 08:39:55 PDT 
Created attachment 462416 [details]
Screenshot of Safari Technology Preview web inspector

Safari Technology Preview 153 (Safari 16.0, WebKit 17615.1.4.1) on macOS 12.6 (21G115)

When I'm debugging iOS Safari (iPad) with the Safari Technology Preview web inspector on Mac, element selection is not working. It does work with regular Safari 16.0 (17614.1.25.9.10, 17614) on Mac, so it appears to be a regression in Safari Technology Preview.

Steps to reproduce:
1) Open Mobile Safari on iPad
2) Open https://webkit.org/
3) Open Safari Technology Preview 153 on Mac
4) In the Develop menu, select the webkit.org page on iPad
5) Select the web inspector Elements tab
6) Press command-f to find
7) Enter "more blog posts" and press return

Expected results: The "More Blog Posts" link is selected in the Elements tab.

Actual results: The "More Blog Posts" link is not selected in the Elements tab, although the search field does find 1 match.

This bug also affects "Start element selection", which doesn't seem to work either.

The bug does not affect inspecting https://webkit.org/ or other pages in a native Mac browser tab in Safari Technology Preview 153. The bug only affects inspecting Mobile Safari.
Comment 1 Patrick Angle 2022-09-20 19:55:30 PDT 
The lack of the "Not found" string next to the search field would suggest we are failing to even perform the search, and the inability to enter element selection mode is most likely related. I wasn't readily able to reproduce, but perhaps the iPadOS version matters – what version of iPadOS is your iPad running?
Comment 2 Radar WebKit Bug Importer 2022-09-20 19:55:52 PDT 
<rdar://problem/100203923>
Comment 3 Jeff Johnson 2022-09-20 20:08:19 PDT 
(In reply to Patrick Angle from comment #1)
> I wasn't readily able to reproduce,
> but perhaps the iPadOS version matters – what version of iPadOS is your iPad
> running?

I can reproduce with today's beta iPadOS 16.1 (20B5050f) and with the public release iOS 16.0 (20A362) on iPhone. I can't reproduce with the public release iOS 15.7 (19H12) on iPhone.
Comment 4 Patrick Angle 2022-09-21 16:12:55 PDT 
Thank you for the version info. After a bit of experimenting I am able to reproduce so long as I have installed and enabled the "Stop the Madness" extension on the iOS or iPadOS device. It appears Web Inspector is missing a chunk of the DOM tree (that is still being rendered correctly) when I've enabled the extension. I'm going to need to investigate a bit further; I suspect this is not unique to this extension.
Comment 5 Jeff Johnson 2022-09-21 16:25:19 PDT 
(In reply to Patrick Angle from comment #4)
> Thank you for the version info. After a bit of experimenting I am able to
> reproduce so long as I have installed and enabled the "Stop the Madness"
> extension on the iOS or iPadOS device. It appears Web Inspector is missing a
> chunk of the DOM tree (that is still being rendered correctly) when I've
> enabled the extension. I'm going to need to investigate a bit further; I
> suspect this is not unique to this extension.

I just installed Safari Technology Preview 154, and I can reproduce with all extensions disabled, so I wonder whether having the extension enabled was only a coincidence.
Comment 6 Patrick Angle 2022-09-21 17:07:18 PDT 
(In reply to Jeff Johnson from comment #5)
> I just installed Safari Technology Preview 154, and I can reproduce with all
> extensions disabled, so I wonder whether having the extension enabled was
> only a coincidence.

Ah, it now readily reproduces even without any extensions enabled. Not sure what state I was stuck in preventing me from reproducing, but I'm now not stuck in that state. I see the issue too...

Thank you for following up!
Comment 7 Patrick Angle 2022-09-21 17:13:51 PDT 
Pull request: https://github.com/WebKit/WebKit/pull/4585
Comment 8 EWS 2022-09-21 19:16:01 PDT 
Committed 254744@main (467145024522): <https://commits.webkit.org/254744@main>

Reviewed commits have been landed. Closing PR #4585 and removing active labels.