1395536 - Firefox is running slow with NVDA and Youtube

Status: RESOLVED WORKSFORME

(Core :: Disability Access APIs, defect, P2)

Description

[roxleitan]

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20170830220349

[Affected versions]:
Nightly 57.0a1

[Affected platforms]:
Windows 10 x64, Windows 10 x86, Windows 7 x86

[Steps to reproduce]:
1.Enable NVDA
2.Enable KAV 10.3.0
3.Launch Nightly 57.0a1 with a new profile
4.Open websites with media ( e.g. youtube.com)

[Expected result]:
The websites are displayed without issues

[Actual result]:
Firefox is running very slow

Comment 1

[David Bolter [:davidb] (NeedInfo me for attention)]

Roxana, is the problem different if KAV is not enabled?

Comment 2

[roxleitan]

Tested on latest Nightly 58.0a1 (Build ID:20170928220658)on Windows 10 with Kaspersky antivirus on and off and is no difference.

But FF is not that slow like it was when I filed the bug. I think because the fix for bug 1384336 was backed out (comment 32 from bug 1384336).

Please note that on Windows 7, FF was slower than on Win 10 (on Nightly 57.0a1), but I cannot test on Win 7 with KAV off(due to security policy).

Comment 3

[Bob Owen (:bobowen)]

Roxana - if you set the pref dom.ipc.useNativeEventProcessing.content to false (and restart), can you reproduce this again?

Comment 4

[roxleitan]

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:59.0) Gecko/20100101 Firefox/59.0
Build ID: 20171211220110

I reproduced the issue on Windows 10 x64 using Nightly 59.0a1 with pref dom.ipc.useNativeEventProcessing.content set to False, NVDA and KAV enabled.

Comment 5

[Bob Owen (:bobowen)]

(In reply to [e-mail] from comment #4)
> Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:59.0) Gecko/20100101
> Firefox/59.0
> Build ID: 20171211220110
> 
> I reproduced the issue on Windows 10 x64 using Nightly 59.0a1 with pref
> dom.ipc.useNativeEventProcessing.content set to False, NVDA and KAV enabled.

Does this happen without KAV?
Things seem pretty much the same for me with it enabled or disabled on the latest Nightly, but I don't have Kaspersky.

Comment 6

[roxleitan]

Mozilla/5.0 (Windows NT 10.0; rv:59.0) Gecko/20100101 Firefox/59.0 
Build ID:20171214220032

I reproduced the issue on Windows 10 x86 using Nightly 59.0a1 with Kaspersky disabled and NVDA enabled, with and without pref dom.ipc.useNativeEventProcessing.content.
I tested on youtube page; the browser is running slow when scrolling down the page, sometimes the sound is blocked for few seconds.  

Tested again on Windows 10 x64 with the latest Nightly build and the issue is a bit intermittent(there are time periods in which the video seems ok and others in which it lags horribly - I didn't identify any pattern related to this).

Comment 7

[Bob Owen (:bobowen)]

(In reply to [e-mail] from comment #6)
...
> I reproduced the issue on Windows 10 x86 using Nightly 59.0a1 with Kaspersky
> disabled and NVDA enabled, with and without pref
> dom.ipc.useNativeEventProcessing.content.

Sorry, just to be clear, are you saying that you are getting the problem and that the dom.ipc.useNativeEventProcessing.content makes no difference or are you saying that you only get it with dom.ipc.useNativeEventProcessing.content set to false?

Comment 8

[roxleitan]

Hi Bob,
Yes, I reproduced the issue(described in comment 6) and the dom.ipc.useNativeEventProcessing.content makes no difference.

Comment 9

[Bob Owen (:bobowen)]

Thanks Roxana.

Jamie - I'm guessing that there might already be a different bug this should block or that is a duplicate.

Comment 10

[James Teh [:Jamie]]

I'm not aware of any bug specifically covering this. Note that a lot of the performance issues with Firefox and NVDA are fixed in 58/59 (as compared with 57). If I understand correctly, this bug seems to be somewhat specific to Youtube (and perhaps other sites with media). I'm narrowing the scope to just cover Youtube for now; we can deal with other specific use cases in follow ups if necessary.

(In reply to [e-mail] from comment #6)
> I tested on youtube page; the browser is running slow when scrolling down
> the page, sometimes the sound is blocked for few seconds.  

1. When you say "scrolling down the page", do you mean with the mouse or with the arrow keys? (The arrow keys are overridden by NVDA to navigate in "browse mode", which is why this is relevant.)
2. If you scroll while the video is paused, do you seem the same slowness?
3. Do you see slowness/video choppiness when you *aren't* scrolling?

Comment 11

[roxleitan]

Attachment: 2018-01-05_11h39_31.mp4

Comment 12

[roxleitan]

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:59.0) Gecko/20100101 Firefox/59.0  
Build ID: 20180104220114

> 1. When you say "scrolling down the page", do you mean with the mouse or
> with the arrow keys? (The arrow keys are overridden by NVDA to navigate in
> "browse mode", which is why this is relevant.)

I scroll the page using the mouse wheel/dragging the scrollbar.

> 2. If you scroll while the video is paused, do you seem the same slowness?
Yes. the browser is running slow even if the video is paused. Please see the attached screencast.

> 3. Do you see slowness/video choppiness when you *aren't* scrolling?

Without scrolling, I don't see slowness/video choppiness. But if I click "play next video" button for more than 3 videos, I see video choppiness and the video resolution is low for a while. (please see "youtube+NVDA video resolution" attachment)

Comment 13

[roxleitan]

Attachment: youtube+NVDA video resolution.png

Comment 14

[alexander :surkov (:asurkov)]

setting as P2, Jamie, please adjust is if necessary

Comment 15

[James Teh [:Jamie]]

Marco, can you reproduce this now? While I'm not sure exactly what fixed this (there are many things it could be, including fixes in Firefox a11y, the NVDA vbuf speed-ups or even changes in Youtube itself), Youtube seems pretty snappy for me now with Firefox + NVDA.

Comment 16

[Marco Zehe (:MarcoZ)]

I don't think I could ever reproduce this. For me, Youtube was always quite OK even in the not so glorious early Quantum days.

Comment 17

[James Teh [:Jamie]]

Okay. I was at one point seeing really nasty performance problems with Youtube, but I'm not now. Given the lack of activity on this bug and that neither of us can reproduce this now, I'm closing as worksforme.