1770592 - document.adoptedStyleSheets is not iterable in a content script

Status: NEW

(WebExtensions :: Untriaged, defect, P3)

Description

[Danny Lin]

Attachment: test-bug - iterable - document.adoptedStyleSheets.zip

User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:100.0) Gecko/20100101 Firefox/100.0

Steps to reproduce:

1. Download and install the attchment as a temporary add-on.
2. Visit https://example.com and open the inspector from the tab.
3. Click the browser action.

Actual results:

"document.adoptedStyleSheets is not iterable" is thrown at for (... of document.adoptedStyleSheets)

(tested on Firefox 101.0b9)

Expected results:

No error should occur when running for (... of document.adoptedStyleSheets)

Comment 1

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

The Bugbug bot thinks this bug should belong to the 'WebExtensions::Untriaged' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Alex Cornestean]

Hello,

I reproduced the issue on the latest Nightly (102.0a1/20220522190601) and Beta (101.0b9/20220519220322) and pretty sure on Release (100.0.220220519220738) as well – an error is thrown but it’s a bit different from what occurs on Nightly and Beta.
Tested under Windows 10 x64 and Ubuntu 16.04 LTS.

On Nightly and Beta, clicking the browser action will throw a TypeError: document.adoptedStyleSheets is not iterable in the web console, while on Release, clicking the browser action will throw a TypeError: document.adoptedStyleSheets is undefined.

For further details, please see the attached screenshots.

Note: I will be marking only Nightly and Beta as affected at the moment, as only there did the bug manifest fully as described.

Comment 3

[Alex Cornestean]

Attachment: Nightly&Beta.png

Comment 4

[Alex Cornestean]

Attachment: Release 100.0.2.png

Comment 5

[Danny Lin]

@Alex Cornestean:
Thank you for confirmation. document.adoptedStyleSheets is not implemented in Firefox 100.*, so it's unrelated with this issue.

Comment 6

[Rob Wu [:robwu]]

The feature was enabled by default in 101 (bug 1644102).

Emilio, this looks like a XrayWrapper issue. I don't know what an ObservableArray is; could this be caused by bug 1023984 (i.e. should it depend on that bug)?

Comment 7

[Rob Wu [:robwu]]

@emilio, See question in comment 6

Comment 8

[Emilio Cobos Álvarez (:emilio)]

This is basically bug 1751346.

Comment 9

[tophf]

Could you raise severity/priority? adoptedStyleSheets is completely unusable in a content script regardless of iterators. The only workaround is wrappedJSObject but it's unsafe.