1789236 - Allow the inspection of the initial about:blank

Status: RESOLVED FIXED

(DevTools :: Framework, defect, P2)

Description

[Henri Sivonen (:hsivonen)]

Currently, the Inspector deliberately makes the DOM of the initial about:blank uninspectable: https://searchfox.org/mozilla-central/rev/1d861901b6682ef2e191b9f7683eb267bdd131e2/devtools/server/actors/watcher/browsing-context-helpers.jsm#261-284

With bug 543435, the initial about:blank may become longer-lived, which means that it will be easier to get to a state where there's a rendered iframe that shows content that is invisible to the Inspector.

The code that currently makes the initial about:blank uninspectable needs revision to allow the user to expect everything that the user can see rendered post- bug 543435.

(I will provide a test case once bug 543435 is further along. Filing this now to have a bug number on file for intent to prototype.)

Comment 1

[Julian Descottes [:jdescottes]]

Moving this to framework, as it's not really inspector specific.

Comment 2

[Julian Descottes [:jdescottes]]

Hi Henri,

Trying to scope a bit the work for DevTools, we should clarify which documents will be impacted by the changes on bug 543435.

The title of the bug mentions iframes, and typically for us it should be easy to relax our checks for iframes. However, if this also impacts top level documents, it might have more impacts on our side, and we would have to plan accordingly. Can you confirm if the change only affects iframes?

I will provide a test case once bug 543435 is further along.

This will be super helpful, thanks!

Comment 3

[Henri Sivonen (:hsivonen)]

Bug 543435 will also make it possible for the initial about:blank to remain rendered after window.open(), so this isn't limited to iframes.

Comment 4

[Julian Descottes [:jdescottes]]

Keeping the bug in triage, until someone has time to test against devtools to check current breakage. Otherwise it would be great if the blocking bug can land independently and then we can fix DevTools afterwards.

Typical expected breakage: loading a new iframe / window.open on about:blank might no longer be debuggable.

Comment 5

[Henri Sivonen (:hsivonen)]

This is now fixed in the patch for bug 543435.

Comment 6

[Henri Sivonen (:hsivonen)]

Specifically, the inspection of the initial about:blank is enabled if the initial about:blank has been navigated to.