User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:44.0) Gecko/20100101 Firefox/44.0 Build ID: 20160210153822 Steps to reproduce: This can be reproduced by visiting the developer's demos... the issue is not present with other browsers like Edge, Explorer and Chrome: http://wowslider.com/it/banner-maker-geometric-kenburns-demo.html Actual results: Images stuttering Expected results: Images not stuttering :-)

The slideshow is completely smooth on my side with FF44 on Win 7. Could you test with a fresh profile, please. https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

Sure :-) I've created a new profile but the stuttering is still there... I see you are on Win 7 while I'm on Win 10 Thanks

Could you test with HWA disabled (restart FF): https://support.mozilla.org/en-US/kb/forum-response-disable-hardware-acceleration

Bravo :-) you tracked it, no stuttering with hardware acceleration disabled. Problem is that nobody is going to disable it when it is enabled by default so it still is a bug from my point of view :-(

I attached a screencast showing the display glitch during the slideshow.

Excellent, it speaks for itself :-) Am I supposed to do something or this is all?

It's an issue with vsync refresh. To reproduce it, you can resize the browser window from bottom right then expand again the window. Reg range: https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=a4ac07b1a28b535c10fce2989a4e5c52d37ecf35&tochange=0f1095c9567fbfdb5fa105905c8f9b1f054af761

Does this happen on nightly? When you say stuttering, do you mean that it isn't smooth or the sometimes random flashes that happen?

The transition between 2 pictures or image animations in the slideshow are smooth, but there are some flashes periodically, you can see the previous picture during a few ms. In the screencast I attached, it's obvious at 15 sec.

I forgot to say it happens with Nightly too, especially with e10s disabled.

I can also reproduce the problem. Mozilla/5.0 (Windows NT 6.1; WOW64; rv:47.0) Gecko/20100101 Firefox/47.0 ID:20160229030448 See capture: https://www.youtube.com/watch?v=2BXhfR99e0c

(In reply to Alice0775 White from comment #12) > I can also reproduce the problem. > Mozilla/5.0 (Windows NT 6.1; WOW64; rv:47.0) Gecko/20100101 Firefox/47.0 > ID:20160229030448 > > See capture: https://www.youtube.com/watch?v=2BXhfR99e0c This seems to be another problem. I filed a new Bug 1252275.

This is an interesting bug. I used the visual studio frame capture and what seems to be happening is that during some animations, it's actually rendering one frame of a different image rather than animating the current image. This happens with or without hardware acceleration, also seems to be backend independent (see bug 1252275). I also disabled OMTA and that didn't seem to matter at all. I also tried looking at the JS source, and it is minified, which makes it a lot harder to see what the app itself is doing :/.

(In reply to Mason Chang [:mchang] from comment #14) > This is an interesting bug. I used the visual studio frame capture and what > seems to be happening is that during some animations, it's actually > rendering one frame of a different image rather than animating the current > image. This happens with or without hardware acceleration, also seems to be > backend independent (see bug 1252275). I also disabled OMTA and that didn't > seem to matter at all. > > I also tried looking at the JS source, and it is minified, which makes it a > lot harder to see what the app itself is doing :/. If you think it is worth I can try contacting the developers asking if they want to support...

I can only reproduce this with the first animation effect. The other effects such as "turn" and "shift" are not flashing for me. Is this the case for you?

Yes, same with me... no flashing with "turn" and "shift" effects

(In reply to Mason Chang [:mchang] from comment #17) > I can only reproduce this with the first animation effect. The other effects > such as "turn" and "shift" are not flashing for me. Is this the case for you? Sorry, I do not understand the terms. What is "first animation effect", "turn" and "shift" effects? Anyway I can reproduce Bug 1252275, the glitch is appears during animation.

"turn" and "shift" are effect options of the slideshow (on the website, you can select them). Yes, the issue appears only with the default option when the site is initially loaded.

(In reply to Loic from comment #20) > "turn" and "shift" are effect options of the slideshow (on the website, you > can select them). Yes, the issue appears only with the default option when > the site is initially loaded. Thanks. Yes, same with me too.

Given that this is happening on all platforms / configurations, with different regression ranges, I suspect that this isn't actually related to the vsync refresh driver, but instead is some deep bug either in the application or gecko that happens at certain times.

(In reply to Flavio from comment #15) > (In reply to Mason Chang [:mchang] from comment #14) > > This is an interesting bug. I used the visual studio frame capture and what > > seems to be happening is that during some animations, it's actually > > rendering one frame of a different image rather than animating the current > > image. This happens with or without hardware acceleration, also seems to be > > backend independent (see bug 1252275). I also disabled OMTA and that didn't > > seem to matter at all. > > > > I also tried looking at the JS source, and it is minified, which makes it a > > lot harder to see what the app itself is doing :/. > > If you think it is worth I can try contacting the developers asking if they > want to support... Sure that would be helpful. Do you have the developers contact info? Or are you trying to go through their support channels? I didn't see any good contact email other than support@wowslider. If you have the developer's email, can you please tell them to email me or you can email me to share their emails. Let's keep their info private since it doesn't seem to be public. Thanks!

> Sure that would be helpful. Do you have the developers contact info? Or are > you trying to go through their support channels? I didn't see any good > contact email other than support@wowslider. If you have the developer's > email, can you please tell them to email me or you can email me to share > their emails. Let's keep their info private since it doesn't seem to be > public. Thanks! Yes, I've emailed them asking that they either email you or they give me the developer's email... I'll update you a.s.a.p

I can no longer reproduce this on the latest nightly (March 9th), which I think is due to bug 1225934. Can you reproduce this on today's nightly?

still broken with e10s on/off and the latest nightly

Just downloaded 45.0 and it is still broken with hardware acceleration enabled as default... if disabled it is OK

Sorry, the latest nightly here - https://nightly.mozilla.org/

Thanks, I did'nt know about that :-) Now running Nightly and the result is the same of 45.0... still broken if hardware acceleration is enabled but OK if is not. The good news is that hardware acceleration is not enabled by default in this Nightly build.

Oh? How come hardware acceleration is disabled for you in nightly? Can you attach your about:support please?

about:support as requested by MChang

(In reply to Mason Chang [:mchang] from comment #30) > Oh? How come hardware acceleration is disabled for you in nightly? Can you > attach your about:support please? I've attached about:support above At Nightly installation I had checked and HA was disabled... as a result I found no issues while if I enable hardware acceleration the problem is still there :-( At least this is what I see with my machine, is it different in your case?

Err sorry, can you go to about:support in the URL bar and click "copy raw data to clipboard" and attach that here as an attachment please? Can you also try creating a new profile before doing that?

Sorry... I have now attached the raw data, unfortunately I have not been able to create a new profile as I had done before 'cause this time when I entered "firefox.exe -P" in the Run dialog box I get an error message that firefox.exe has not been found. I'm now on the new nightly 480a1

Now on 480a1 I see strong flickering even with hardware acceleration disabled... http://donatachiesa.com/#portfolio what seems to help is disabling multi-process Nightly in the General settings

P.S. help... but not solve

But if both multi-process and hardware acceleration are disabled it seems to me that everything is OK... can somebody disable both and tell if he finds the same?

See https://bugzilla.mozilla.org/show_bug.cgi?id=1252275#c9