1293731 - CSS target selector is reset on print

Status: NEW

(Core :: Printing: Output, defect)

Description

[douman]

Attachment: lang.html

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:48.0) Gecko/20100101 Firefox/48.0
Build ID: 20160726073904

Steps to reproduce:

1. Open HTML in Firefox https://drive.google.com/file/d/0B7w3ZGc8CTgqMUxWZkdONlhyZWM/view
2. See two lines of "English text"
3. Choose 'ru'. Text is changed thanks to CSS target selector.
4. Open Print Preview


Actual results:

Preview contains original two lines of "English text".
It is suspected that Print Preview resets CSS target selector and update page before showing preview.


Expected results:

Print Preview should be the same as page being printed.
I.e. there should be no "English text" but two lines of "Русский текст"

Comment 1

[Vlad Bacia-Mociran [:VladB]]

User Agent: Mozilla/5.0 (Windows NT 10.0; rv:51.0) Gecko/20100101 Firefox/51.0
Build ID: 20160811030201

I have tested your issue on latest Firefox release (v48.0) and latest Nightly build (v51.0a1) and managed to reproduce it. On the Firefox release build, after opening Print Preview the text from the HTML page is displayed in English. On latest Nightly, the tab crashes.

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

It's not completely clear to me what should happen here.  Is printing supposed to print the entire page or the current target?  I suppose we could try to preserve the target when printing, but without actually scrolling to it.  Is there some other expectation that would break as a result of that, though?

And if we want to switch to a model where we're printing the current view of the page, how many other things do we need to change?

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

(That said, trying to preserve the target probably is the right thing to try to do here.)

Comment 4

[douman]

I'm sorry it is not clear enough.
The expected behavior is to print what user requested to print.

I.e. all changes that were made through CSS target selectors should be preserved when user request to print page (or any other ways to change the content without reloading).
Printing should capture the current content of page, not original.