Bug 245411

Summary:

Multiple picture sources downloading when page is served as XHTML

Product:

WebKit

Reporter:

Robin Whittleton <robin>

Component:

Images

Assignee:

Nobody <webkit-unassigned>

Status:

NEW ---

Severity:

Normal

CC:

ahmad.saleem792, ap, cdumez, sabouhallawa, simon.fraser, webkit-bug-importer

Priority:

Keywords:

InRadar

Version:

Other

Hardware:

Mac (Intel)

OS:

Other

See Also:

https://bugs.webkit.org/show_bug.cgi?id=159484

Attachments:

Description	Flags
XHTML variant that demonstrates the problem	none
HTML variant that works correctly	none

Description Robin Whittleton 2022-09-19 23:18:10 PDT

Created attachment 462466 [details]
XHTML variant that demonstrates the problem

First up, this is quite possibly a dupe of bug #159484, but as the trigger is different I’ll start with filing this issue separately.

Given a page with a picture element with a source element that references a different resource to the img element, both referenced resources will be downloaded if the page is served as an XHTML document with the appropriate xmlns.

I’ve attached a couple of test files that demonstrate the problem.

This was observed in the wild on https://standardebooks.org/ebooks, which doesn’t contain any JS (trigger from bug #159484) and is served as XHTML.

Comment 1 Robin Whittleton 2022-09-19 23:18:29 PDT

Created attachment 462467 [details]
HTML variant that works correctly

Comment 2 Ahmad Saleem 2022-09-23 13:23:32 PDT

Only difference I can find between these two test is:

<html xmlns="http://www.w3.org/1999/xhtml">

vs

<html>

and both have issues while pasting the code in W3C validator:

https://validator.w3.org/#validate_by_input

- Can you share an example with working images in it and reproducible test case in both cases, I don't get any difference. Thanks!

Comment 3 Alexey Proskuryakov 2022-09-24 16:18:39 PDT

What's important here is that the attachments are served with different content types. application/xhtml+xml means that the document is handled as XHTML.

To see the problem, one needs to check errors in Web Inspector. One subresource loading error means passing; two errors means failing. This does reproduce.

Comment 4 Ahmad Saleem 2022-09-24 16:20:10 PDT

(In reply to Alexey Proskuryakov from comment #3)
> What's important here is that the attachments are served with different
> content types. application/xhtml+xml means that the document is handled as
> XHTML.
> 
> To see the problem, one needs to check errors in Web Inspector. One
> subresource loading error means passing; two errors means failing. This does
> reproduce.

Thanks for your input.. New learning for me. Will account for in future testing. :-)

Comment 5 Radar WebKit Bug Importer 2022-09-26 23:19:18 PDT

<rdar://problem/100444926>

Comment 6 Robin Whittleton 2022-09-26 23:25:43 PDT

Note: standardebooks.org (referenced in the original comment) has now been adjusted to not serve any source elements to Safari, effectively bypassing this problem. The bug still stands with the testcases.