791686 - png transparent alpha channel is displayed as a white background when using "view image" menu item

Status: VERIFIED FIXED

(Firefox :: Untriaged, defect)

Description

[Giuliano Masseroni [:jooliaan]]

User Agent: Mozilla/5.0 (Windows NT 6.0; rv:15.0) Gecko/20100101 Firefox/15.0.1
Build ID: 20120905151427

Steps to reproduce:

Just as an instance go to www.mozillaitalia.org then point your mouse on the Paypal Foxkeh. Right click and choose View Image 


Actual results:

The transparent alpha channel of that png is displayed as a white background.
(This happens with all the png with transparent alpha channel I have found.)


Expected results:

The transparent alpha channel of the png should be displayed as a transparent background.

Comment 1

[Loic]

It's the normal behavior of Firefox to avoid user confusion when a transparent image has elements (like black letters) similar to the gray background. In this case, the background becomes white (as previously when the entire background was white) instead of staying gray.

Comment 2

[Giuliano Masseroni [:jooliaan]]

In Fx 14 and earlier it was not this way.

Comment 3

[Loic]

It's new in FF15.
See https://addons.mozilla.org/en-US/firefox/addon/transparent-standalone-imag/ to change this behavior.

Comment 4

[Matthias Versen [:Matti]]

a white background is the result of bug 754133

Comment 5

[Giuliano Masseroni [:jooliaan]]

I drive the official Italian Support Forum and let me say that many people are not happy with this "new feature". Believe me.
IMO, the best compromise for trying to make everybody satisfied is -at least- to follow the suggestion given by  Alfred Kayser in comment 4 for bug 754133

Comment 6

[Alfred Kayser]

Attachment: Foxkey standalone view on patterned background

The question is really what color to use for the background of transparent images: white gives the impression that the image is not transparent, but darkgrey looks somewhat better (as done by that extension). Viewing images (such as this foxkeh) standalone is to be considered a kind of debug/analysis function (not normal browsing), and in that case using a patterned background (like in Nautipolis) is more suitable.

Comment 7

[Matthias Versen [:Matti]]

Giuliano: Loic and I'm are only contributors like you and I'm sure that not many people are reading this bug. Either CC people, comment in bug 754133 or in the newsgroups that Boris mentioned in comment#0 of that bug.