957054 - Don't preload scripts with unknown types

Status: NEW

(Core :: DOM: HTML Parser, task, P3)

Description

[Henri Sivonen (:hsivonen)]

See
https://code.google.com/p/chromium/issues/detail?id=329531

Comment 1

[Boris Zbarsky [:bzbarsky]]

Note discussion at https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/eu57SCNltls

Comment 2

[Jens Stutte [:jstutte]]

Bulk-downgrade of unassigned, 4 years untouched DOM/Storage bugs' priority.

If you have reason to believe this is wrong (especially for the severity), please write a comment and ni :jstutte.

Comment 3

[Henri Sivonen (:hsivonen)]

Chrome has fixed their corresponding bug: https://bugs.chromium.org/p/chromium/issues/detail?id=626321

Comment 4

[yanshrey]

If chrome as fixed their corresponding bug does it also gets fixed on mozilla? If not then i would like to work on this bug.

Comment 5

[Henri Sivonen (:hsivonen)]

(In reply to yanshrey from comment #4)

If not then i would like to work on this bug.

That would be great. See https://searchfox.org/mozilla-central/rev/1ebc9745be02eebf7a694f5c527a44a045b8c97a/parser/html/nsHtml5TreeBuilderCppSupplement.h#207 for the starting point.

Comment 6

[james]

Hi,
Is anyone still working on this bug?
If not want to give it a shot

Comment 7

[yanshrey]

I was looking into but but you can also go ahead and try it.
Check comment #5

Comment 8

[Henri Sivonen (:hsivonen)]

Fixing bug 1848311 would have the side effect of fixing this.

Comment 10

[Henri Sivonen (:hsivonen)]

Not only should we not preload unknown type, we should not create speculations when seeing unknown types.

From the bug I marked as duplicate:

We should check for IE event handler scripts and unsupported type/language combinations in the HTML parser already (not just in ScriptLoader) to avoid creating speculations or preloads for scripts that will not execute anyway.

Comment 11

[Mathew Hodson]

Attachment: WIP: Bug 957054 - Don't preload scripts with unknown type

Based on
https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script

This affects mSpeculativeLoadQueue. I didn't change the behavior of
mCurrentHtmlScriptCannotDocumentWriteOrBlock.

Comment 12

[Mathew Hodson]

I'm currently stuck trying to implement your suggestion to handle ScriptKind::eEvent like mozilla::dom::IsScriptEventHandler does. There isn't an nsHtml5AttributeName::ATTR_EVENT that I would need to detect an event attribute on a <script> element.

Comment 13

[Henri Sivonen (:hsivonen)]

Sorry about the delay. Indeed, ATTR_EVENT is needed and missing. I'm adding it in bug 1884108.

Comment 14

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

This good-first-bug hasn't had any activity for 2 months, it is automatically unassigned.
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