1415111 - Zoom preferences lost after restart

Status: RESOLVED INVALID

(Firefox :: Session Restore, defect, P3)

Description

[Benjamin Bouvier [:bbouvier] (inactive)]

I'm using Firefox Nightly (last version as of today).

STR:

- set a zoom value on a website
- restart nightly

Observed:

zoom value is lost at restart on the website.

Expected:

zoom value is memoized and reused on the website.

This is a recent regression, I think it wasn't happening one or two weeks ago.

Comment 1

[Benjamin Bouvier [:bbouvier] (inactive)]

Reproduces in safe mode with addons disabled.

Comment 2

[Valentina Claudia Ona]

I can't reproduce this issue and I using latest Nightly with Build ID 20171107220115. Can you please tell me which versions are affected to set the flags?

Comment 3

[Benjamin Bouvier [:bbouvier] (inactive)]

(In reply to Valentina Claudia Ona from comment #2)
> I can't reproduce this issue and I using latest Nightly with Build ID
> 20171107220115. Can you please tell me which versions are affected to set
> the flags?

I'm using the latest Nightly (20171108110838).

I've found out two things:

1) this doesn't happen on another machine, so this might be profile specific :/
2) i can repro in an even simpler way, by just opening a page, setting a zoom, closing this page, reopening the same URL (and the zoom is lost). I will investigate with mozregression.

Comment 4

[Benjamin Bouvier [:bbouvier] (inactive)]

Aouch, I found out what's going on here. After trying mozregression a few times, the issue was reproducing again and again with my profile, even on dates I was sure it should have been working.

Found out about a pref called "browser.zoom.siteSpecific", which sounded like what I wanted, I've looked it up on searchfox and found the following:

http://searchfox.org/mozilla-central/source/dom/html/ImageDocument.cpp#50-54

Indeed I did have privacy.resistFingerprinting set to true, to try it the last few days, so I guess this was expected in some form. Setting it back to false made site-specific zooms work again. Thus closing as invalid, since it's expected behavior. Perhaps it should be better documented, i.e. when privacy.resistFingerprinting is set to true, we should let the user know what tradeoffs they should be aware of?