1860821 - FaviconLoader does not fall back to favicon.ico when other icon URLs are 404 on icloud.com

Status: NEW

(Firefox :: Tabbed Browser, defect)

Description

[Kestrel]

Attachment: No attempt to load favicon.ico

STR:

1. Visit https://www.icloud.com.

Favicon in tab is missing.

<link rel="apple-touch-icon" sizes="180x180" href="apple-touch-icon.png">
<link rel="icon" type="image/png" sizes="16x16" href="favicon-16x16.png">
<base href="/system/icloud.com/2326Project187/en-us/">
<link rel="icon" href="/favicon.ico">

The first two icons appear in the Network Monitor as missing (404), /favicon.ico exists but there is no network request for it.

Chromium uses /favicon.ico without issues.

First regression:
First attempt fails to load favicon, refreshing works.
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=179dae92e4d794e7f45ad080ff01908c80691f31&tochange=40df5dd35fdb7ce3652fe4448ac8961c075c928e

Possibly regressed by Bug 1403829.

Second regression:
All attempts fail to load favicon, refreshing page multiple times does not work.
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=8f49b2a0e003fe63da04aab9714ddc62bcb7a65c&tochange=28ad9a9e95d518e1163e550ae19c972aabb44df5

Possibly regressed by Bug 1453751.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:dao, could you have a look please?

For more information, please visit BugBot documentation.

Comment 2

[Dão Gottwald [:dao]]

(In reply to Kestrel from comment #0)

First regression:
First attempt fails to load favicon, refreshing works.
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=179dae92e4d794e7f45ad080ff01908c80691f31&tochange=40df5dd35fdb7ce3652fe4448ac8961c075c928e

Possibly regressed by Bug 1403829.

mak, what do you think?

Second regression:
All attempts fail to load favicon, refreshing page multiple times does not work.
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=8f49b2a0e003fe63da04aab9714ddc62bcb7a65c&tochange=28ad9a9e95d518e1163e550ae19c972aabb44df5

Possibly regressed by Bug 1453751.

mossop?

Comment 3

[Dave Townsend [:mossop]]

I don't think it is worth identifying the exact regressor for a five year old issue. The fundamental issue is that we only attempt to try the root favicon when there are no other icons present during the initial load of the DOM.

It would be good to understand what other browsers do here. If a developer has provided a specific icon in the html, even if it is broken should we load favicon.ico? What if the developer has provided multiple icon options, should we only fallback to favicon.ico or should we also attempt the other icons in the doc which I don't believe we do currently?

Comment 4

[Marco Bonardo [:mak]]

I agree with Dave, the regressors are just telling me we don't have a good fallback in case of network errors.
From the user point of view, I think we should fallback to any recognizable icon. I suspect the user doesn't mind which one.
As there's no standard to be followed about this, we can try to be compatible with other browsers behavior, thus build a test site and test Safari and Chrome, at least.