1280349 - Popups are blocked despite blocking is disabled (if opening more popups than dom.popup_maximum, which isn't cleared when disabling the popup blocker from about:preferences)

Status: RESOLVED WONTFIX

(Firefox :: Settings UI, defect)

Description

[macias]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:46.0) Gecko/20100101 Firefox/46.0
Build ID: 2016042500

Steps to reproduce:

I have a script that opens K (say 20) popups. The Firefox settings regarding blocking popups are disabled (i.e. all popups are allowed). I still keep some exceptions for blocking popups, but since the main checkbox is disabled, they should be ignored (right?).


Actual results:

When running the script Firefox on random blocks 2, 5, 10 of the popups and shows the notification about it allowing me to add exceptions to the blocking filter. The thing is I should not need a filter for popups, because I don't use blocking at all.


Expected results:

When Firefox settings are in mode "don't block popups", then, well, there should be no blocking, every popup should show up no matter what. Firefox should not interfere.

Comment 1

[Loic]

Could you attach a testcase,

Comment 2

[macias]

Attachment: popup_testcase.html

Sure thing, see the attachment, if you don't trust the addresses I put there, please replace them with your own. The concept is, AFAIK, to stress Firefox with opening multiple addresses, so for example with 2 urls you won't see the effect, with 20 -- yes. In my case, 4 urls were blocked.

What to do:
* run Firefox
* make sure the checkbox for blocking popups is disabled (empty) -- so there is no blocking 
* open the page I attached

You should observe:
* Firefox opens multiple tabs -- that's fine
* when you see there is no new tab opened (it should happen after around 2-3 seconds) switch to the first tab
* there should be popup-blocker notification about blocked popups

If the last won't occur, you may have faster computer or something like this, please add more urls to the "addresses" array.

Oh, btw. I use openSUSE 13.2.

Comment 3

[macias]

PS. Just out of curiosity I clicked on the attachment directly without saving it on the disk first. In this case all urls were blocked! So once you review the addresses are not malware or something like this (they are not, but don't trust a stranger on the internet, right :-)) you have even easier way to observe the behaviour, just click LMB on "attachment".

Comment 4

[Loic]

I can't reproduce it with FF47 on Win 7. With pop-up blocker disabled, all websites are open normally.
Did you test with a fresh profile?
https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

Comment 5

[macias]

Attachment: popup_testcase.html

It is just a matter of tipping point, where Firefox will choke with all those urls. So initially FF47 did better (no blocks at start), but I simply added more addresses and reduce interval, and I got plenty of blocked popups.

I did also the test with just created profile (and I disabled blocking, because it is enabled by default), same story.

I attached "updated" script (small interval, more urls).

Comment 6

[:Gijs (he/him)]

Does this still happen without the setTimeout, if you just call window.open directly from the loop, N times for whatever N?

Comment 7

[macias]

If I call `openInNewTab` directly, without using timeout at all, Firefox will block some of the tabs exactly as before.

Comment 8

[:Gijs (he/him)]

Blake or :jst, any idea what's going on here? This looks more like a platform than a frontend issue to me, and #developers said you know the core popup blocking code. :-)

Comment 9

[Justin [:JW_SoftvisionQA]]

When having the popup blocker box checked I get a message saying 37 popups were blocked but when unchecking this box I get only 20 popups.

Comment 10

[:Gijs (he/him)]

(In reply to Justin [:JW_SoftvisionQA] from comment #9)
> When having the popup blocker box checked I get a message saying 37 popups
> were blocked but when unchecking this box I get only 20 popups.

Sure, but there should be 0 blocked popups and no message if popup blocking is disabled...

Comment 11

[Justin [:JW_SoftvisionQA]]

> Sure, but there should be 0 blocked popups and no message if popup blocking
> is disabled...

Correct. This is reproducible. Not sure which component it should be placed in though.

Comment 12

[Blake Kaplan (:mrbkap) (inactive)]

I'll take a look at this.

Comment 13

[Masatoshi Kimura [:emk]]

We have another level of popup spam protection (dom.popup_maximum=20). What happens if this pref is seto to -1 (unlimited)?

Comment 14

[Justin [:JW_SoftvisionQA]]

With dom.popup_maximum=-1 this bug is a works for me.

Comment 15

[:Gijs (he/him)]

(In reply to Masatoshi Kimura [:emk] from comment #13)
> We have another level of popup spam protection (dom.popup_maximum=20). What
> happens if this pref is seto to -1 (unlimited)?

Ugh, I'd forgotten this. Marking as WFM as filed, then.

Comment 16

[macias]

I am a bit puzzled, so user goes to preferences, set "don't block popups" and popups will not be blocked, correct? As the checkbox says.

Please note that the Firefox actions (blocking, offering exceptions, and so on) are wrong.

Comment 17

[:Gijs (he/him)]

(In reply to macias from comment #16)
> I am a bit puzzled, so user goes to preferences, set "don't block popups"
> and popups will not be blocked, correct? As the checkbox says.
> 
> Please note that the Firefox actions (blocking, offering exceptions, and so
> on) are wrong.

Clearly I disagree. :-)
You can fix this for your usecase by going to about:config and changing the preference mentioned in comment 13.

I don't think the UI there should change this preference for you if you disable popups *everywhere*, because the consequences of removing the limit can be severe if you land on trap websites (see deps of bug 432687). I also don't think the edgecase in question is worth adding extra UI for, or trying to explain all the subtleties in the preferences UI. No user application I've ever seen relies on having to open more than 20 popups in succession. If your special script relies on this, you can of course remove the limit yourself at your own risk.

However, in the general case you'd add an exception for a particular domain (rather than disabling popups everywhere), in which case the limit should arguably not apply. That's bug 1176510.

Comment 18

[macias]

My point is, that if popups are blocked because of the limit, there should be notification stating about the limit.

Clear message "You reached XXX limit of popups, those are blocked" is informative, correct, and useful.