1071302 - Popup blocker blocks file open dialogs from input type=file

Status: RESOLVED INVALID

(Firefox :: Untriaged, defect)

Description

[sil-persona]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:32.0) Gecko/20100101 Firefox/32.0
Build ID: 20140830210550

Steps to reproduce:

Visit a site with an input type=file button. Click the button.


Actual results:

Firefox blocks the file dialog from opening, and shows the "Firefox prevented this site from opening a pop-up window" top bar and Preferences button.


Expected results:

A file open dialog is not a pop-up window. It should not be blocked from opening.

Comment 1

[Matthias Versen [:Matti]]

You get the popup warning if you click in this bug report on the "add an attachment" link and select "browse" ?

Comment 2

[sil-persona]

Matthias: I do indeed, yes.

Comment 3

[Mike Conley (:mconley) (:⚙️) (PTO - Dec 21 - Jan 3rd)]

That sounds really awful.

sil - can you try running in safe mode and seeing if the behaviour persists? (Help > Restart with Add-ons Disabled)

Comment 4

[sil-persona]

Have tried restarting with addons disabled and it does not fix the bug.

However! I have had a memory. A while back I was trying to stop intrusive sites which managed to make popups appear even despite the popup blocker. So I poked around at the popup blocker's settings in about:config. It occurs to me that this might have caused the effect. I should say that I can't think of any reason why, whatever preferences changes I make, that a file open dialog should be considered a blockable popup (so that's still a bug, in my opinion), but this may be peculiar to those settings. I do have user_pref("dom.popup_allowed_events", ""); in prefs.js; perhaps this is the cause? (I should note again that I don't think that file open dialogs ought to be a blockable event at all; they're an implementation detail, not a popup.)

Comment 5

[Mike Conley (:mconley) (:⚙️) (PTO - Dec 21 - Jan 3rd)]

According to http://kb.mozillazine.org/Dom.popup_allowed_events, that preference (which I've never heard of until now), is used to filter which events are allowed to open popups.

I agree that file input windows are not in the same realm as traditional popup windows, and it is surprising to me that they'd be considered the same to our popup blocking code.

Can you open about:config, reset that preference to default, and see if the problem goes away? If so, we can file a follow-up bug to investigate why we're equating file inputs with other popups.

Comment 6

[sil-persona]

OK. I confirm that resetting that preference to the default value (which is "change click dblclick mouseup reset submit touchend") stops this problem occurring. I don't know whether it's better to repurpose this bug to be about treating file inputs as popups or file a new one, so I'll leave that to better minds.

Comment 7

[Mike Conley (:mconley) (:⚙️) (PTO - Dec 21 - Jan 3rd)]

Alright, I've filed bug 1071662 to try to eliminate this footgun.