873024 - Changes in site-specific zoom leaks from private into regular browser windows showing the same site

Status: RESOLVED INVALID

(Firefox :: Private Browsing, defect)

Description

[rsx11m]

Private browsing windows are supposed to maintain their own "space" for site-specific settings, which seems to be violated for the following case:

1. Verify that browser.zoom.siteSpecific = true
2. Visit some site and use Ctrl +/- to change its zoom level
3. Right-click on a link that stays within the same site
4. Select "Open Link in New Private Window"
5. New window opens with the same zoom level as chosen in step #2
6. Use Ctrl +/- to change the zoom level in the private window
7. Observe that zoom level in the regular browser window changes as well
8. Click on a local link in the private window to switch the page
9. Private window returns to #2 level whereas regular one stays at #6 level

Expected behavior:

7. Zoom level only changes the view in the private window
9. Zoom level in regular window is not affected by changes in private window

Comment 1

[(no longer active)]

Does the zoom level change in the private window persist in the content prefs database?

Comment 2

[rsx11m]

(Testing on a SeaMonkey trunk build to easier monitor site-preference activities in the Data Manager.)

Good point. Upon further testing, changing the zoom level in either the private-browsing or the non-private window affects the zoom level in both windows. Looking at the Data Manager, each change creates a new entry for browser.content.full-zoom with the current zoom value for that domain. Switching tabs forth and back, only the full-zoom entry for the regular browser window remains, i.e., while changing the zoom in the private window changes it visually for the regular window as well, it indeed won't persist and is restored when switching tabs in the regular window.

Thus, apparently it's mostly a matter of disabling any synchronization of zoom levels from the private-browsing window into other windows.

Comment 3

[(no longer active)]

If we don't persist any data, then everything is working as expected!

Comment 4

[rsx11m]

Interesting, so the change in a private window is /supposed/ to change it in the regular window as well? In that case, I'm not understanding the concept of the private brwosing quite right, where I would assume that any activity and changes specific to a private window remain within the scope of that window (thus, won't leak/affect any other window even if it happens to work on the same site).

Comment 5

[(no longer active)]

(In reply to comment #4)
> Interesting, so the change in a private window is /supposed/ to change it in
> the regular window as well? In that case, I'm not understanding the concept of
> the private brwosing quite right, where I would assume that any activity and
> changes specific to a private window remain within the scope of that window
> (thus, won't leak/affect any other window even if it happens to work on the
> same site).

Private browsing is about not saving local traces that can be used to identify the user's browsing session.

Comment 6

[rsx11m]

Fair enough, thanks!