1416744 - Zoom level is not persisted per website

Status: RESOLVED DUPLICATE of bug 1415111

(Core :: Layout, defect, P3)

Description

[krzysztof.krason]

User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:59.0) Gecko/20100101 Firefox/59.0
Build ID: 20100101

Steps to reproduce:

1. Go to any website
2. Press ctrl + '+' (to increase zoom level) to e.g. 150%
3. Close the website tab
4. Go to the same website



Actual results:

Zoom level of the website is set to 100%


Expected results:

Zoom level should be remembered, so when I go back to given website I should see the zoom level that I set to it (in this case on the second visit it should be 150%).

This worked previously but stopped few (2-3) weeks ago in Firefox Nightly (58), same happens with 59.

Comment 1

[Valentina Claudia Ona]

Thanks for reporting!
I can't reproduce this issue with Nightly 59.0a1 with Build ID 20171113220112.
Could you please try to reproduce in safe mode?
https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode
If you still have the issue please create a new profile, you have the steps here: https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles?redirectlocale=en-US&redirectslug=Managing-profiles#w_starting-the-profile-manager

Comment 2

[krzysztof.krason]

OK, so I tested it in safe mode - same problem.
Using new profile - no problem.

So now the question is what happened to my profile and how to fix it?
Is it possible that I have to many websites with different zoom level and the DB broke?

Comment 3

[Julien Cristau [:jcristau]]

Do you have tracking protection enabled in your profile?

Comment 4

[krzysztof.krason]

Yes, I have it enabled (and also canvas fingerprinting disabled, I don't remember the exact about:config entry for that).

Comment 5

[Julien Cristau [:jcristau]]

I think this might be the same as bug 1415111.

Comment 6

[krzysztof.krason]

Looks like it, but why site specific zoom is tied to resistFingerprinting setting?

Comment 7

[Astley Chen (inactive)]

(In reply to krzysztof.krason from comment #6)
> Looks like it, but why site specific zoom is tied to resistFingerprinting
> setting?

Ethan, do you know why?

Comment 8

[Ethan Tseng [:ethan]]

(In reply to krzysztof.krason from comment #6)
> Looks like it, but why site specific zoom is tied to resistFingerprinting
> setting?

This was implemented in bug 1369357 (Making Firefox not to use site-specific zoom level when 'privacy.resistFingerprinting' is true).
In short, the zoom level is one of the fingerprinting sources, and this behavior is an approach to protect users against browser fingerprinting.

Quoted from the Tor Browser design document [1]:
"7. Monitor, Widget, and OS Desktop Resolution
Both CSS and JavaScript have access to a lot of information about the screen resolution, usable desktop size, OS widget size, toolbar size, title bar size, and OS desktop widget sizing information that are not at all relevant to rendering and serve only to provide information for fingerprinting. Since many aspects of desktop widget positioning and size are user configurable, these properties yield customized information about the computer, even beyond the monitor size."

We have realized this feature annoyed users.
There is a potential solution proposed in bug 1407366.
But we need more time to investigate it. 


[1] https://www.torproject.org/projects/torbrowser/design/#fingerprinting-linkability

Comment 9

[krzysztof.krason]

Thank you for the explanation.