Open Bug 634073 Opened 12 years ago Updated 4 months ago

"http-on-modify-request" is not fired for cached images


(Core :: Graphics: ImageLib, defect)

Windows XP




(Reporter: Honza, Unassigned)


(Whiteboard: [firebug-p1][netmonitor])


(1 file)


You need to enable: browser.dom.window.dump.enabled true

1) Install the attached extension
2) Load
3) Do a non-revalidating reload (press ENTER in address bar)
4) See the system console, it's displaying:
--- observe: http://localhost/firebug/tests/issues/3742/issue3742.html
"http-on-modify-request" are not fired for images.

If you refresh the page by pressing F5 you'll see:
--- observe: http://localhost/firebug/tests/issues/3742/issue3742.html
--- observe: http://localhost/firebug/tests/issues/3742/image1.png
--- observe: http://localhost/firebug/tests/issues/3742/image2.png

Source code of the attached extension is available here:

Whiteboard: [firebug-p1]
Confirming this issue,

For my add-on update at AMO ( I need "http-on-modify-request" working for cached content.

Please also consider to make setResponseHeader working for Content-Length which currently is READONLY and therefore throws NS_ERROR_ILLEGAL_VALUE on modification attempts. Reason: Quite a lot servers send wrongly calculated Content-Length (possibly caused by invalid calculations posted at and elsewhere) which prevents caching (see bug 588507) - but this request probably needs to be filed as another new bug(?).
Whiteboard: [firebug-p1] → [firebug-p1][netpanel]
Whiteboard: [firebug-p1][netpanel] → [firebug-p1][netmonitor]
I can confirm that this is still an issue in Nightly 44.0a1 (2015-09-23).
And of course this is not just affecting Firebug but also the built-in devtools' Network panel.

Component: Networking → ImageLib
Severity: normal → S3
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