Safari scrolling issue

Question

Level 1

8 points

Safari scrolling issue

When I'm using safari on my ipad air 2, I occasionally encounter a scrolling issue on some webpages. When I try to scroll down, the content which is present on the screen will "slide out" on the top, but no new content will slide up from the bottom of the screen. Instead, the screen goes white for a moment, until the content that should have been coming up, is loaded. This is really annoying. Every time I try to scroll down a page, I have to wait until the content show after a second or two. The same thing happens of course when I am at the bottom of a page and try to scroll upwards. This indicates that the problem has nothing to do with bandwidth or any connection-relating problem, since the problem is present even when the page is fully loaded.

The problem is not present on all webpages, but enough pages to make it a real problem for me.

The temporary solution to the problem is to close safari by double clicking the home-button, kill the app, and then reopen safari. Then everything is fine for a while.

Yesterday I reset the ipad and made a new, clean install of ios 9.2.1 via itunes on a computer. Seemed fine for a while, but the problem has now returned...

I have searched different forums. Seems I'm not alone with this problem, but no one has come up with a solution yet, and I haven't seen a good explanation of what may cause this.

Is it software or hardware related. Why isn't it a problem for all ipad air 2/safari users? Is it the content on some webpages that makes this problem occur?

iPad Air 2 WiFi, Cellular, iOS 9.2.1

Posted on Feb 29, 2016 12:19 PM

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Answer 1

Drew Reece

Level 6

10,684 points

Feb 29, 2016 1:33 PM in response to jhros

It would help to know the site addresses so others can test & compare.

Personally I think you are describing something that seems to plague many sites today - adverts & content that is loaded from other servers. A simple test is to install a content blocker to see if the site loads better when the additional resources are blocked.

iOS 9 has content blockers that can be added from the store or try the adblock browser & let us know if it is better.

https://adblockbrowser.org/

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Answer 2

Drew Reece

Level 6

10,684 points

Mar 1, 2016 1:00 PM in response to jhros

These sites all use the 'dynamic image loading' via javascript (boxes that get replaced by images) with other scripts that load adverts etc. It's a process that causes Safari to process lots of data (technically it is the 'javascript engine' doing the work).

I did some tests with the Safari Web inspector on OS X…

tu.no

With JS

155 resources, 3.5MB of data no scripting errors reported by Safari

Without JS

64 resources, 2.04MB of data

db.no

With JS

301 resources, 5.48 MB in total, 5 scripting errors. This site finishes loading - after 20 seconds.

Without JS

37 resources, 923KB in total

nettavisen.no

Tries to load around 20 frames from other sites (mostly google double-click adverts) Loading many of these frames fails at the moment.

With JS

Over 350 resources, 8.66 MB of data with 549 script errors over a period of 1.4 minutes.

The scripts continue to poll in the background, apparently forever…

Without JS

131 resources, 3.13 MB of data

From what I can see you are looking at sites that are heavy in scripts & assets. It is a common issue on the web today, discussed by some web developers…

http://idlewords.com/talks/website_obesity.htm

http://www.soasta.com/blog/page-bloat-average-web-page-2-mb/

It has been going on for years & is getting worse, blocking some of it can help in my experience.

If you still think the iPad(s) are at fault go and see an Apple store, approved service centre or see if others have a better answer.

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Answer 3

Drew Reece

Level 6

10,684 points

Feb 29, 2016 2:37 PM in response to jhros

jhros wrote:

www.tu.no (Norwegian page).

That page took a minute & a half to render in Safari on OS X. It is still loading content in the background even when the progress indicator completes.

It looks like it is loading the images & content via javascript. It loads in fractions of a second if I disable javascript (it seems to have all the content).

I'd contact that site and ask why their scripts are slowing the page load? You could consider using a 'no-script' or javascript blocker for that site if it alters the performance for you, obviously some features require javascript.

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Answer 4

jhros Author

Level 1

8 points

Mar 1, 2016 6:39 AM in response to Drew Reece

I have installed 1Blocker. I'll try that for a while, and I'll also activate script-blocker.

But even if the pages I visit has bugs, I still wonder why this only affects some ipads, and not all. At my working place, we have two ipad air with ios 9.2.1 installed. I have not been able to reproduce the same problems on those ipads. I have visited the same pages with them that I visit with mine. My parents has an ipad air 2, same as mine, but not cellular. No problem with that one either. Is it possible that the memory or some other hardware in my ipad is corrupted, and that my ipad therefore is more likely to run into problems with webpages than other ipads?

The ipads we use at work has of course different apps than my ipad have. But on my ipad, the problem is still present after a fresh installation of ios. If the problem was only software related, then a new install of ios should have solved the problem, I suppose?

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Answer 5

Drew Reece

Level 6

10,684 points

Mar 1, 2016 8:33 AM in response to jhros

iPads have memory (RAM) & storage.

If RAM was 'corrupted' other applications would almost certainly be effected - you haven't mentioned that as a symptom.

When reinstalling iOS Safari would be written to a new part of the storage, the flash media uses 'wear levelling' to ensure no part wears out faster (flash storage has a limited amount of read & write cycles). That means another app would be put onto the 'corrupted' part of the storage. Something else would fail.

I can't see how it is corruption of the storage or RAM.

If you feel like it is a hardware issue take it to an Apple store or to the place you purchased it. You could be right, however my suspicion is that it is the fault of the site. It performs terribly on hardware that is many times faster than your iPad. With scripting disabled it loads very fast. The Safari web inspector shows scripts constantly polling whilst it loads.

I don't know why other models would not show the issue, try running lots of other apps to see if that has any effect, also check how much free storage each iPad has. There can be a number of different factors when comparing the same models.

I'd suggest you contact the site in question & enquire about it - if they respond with 'yes we know, we are working on it' you have a better idea for what is happening for that site.

You are correct that this may not be the issue, it just seems like a possible explanation from my point of view. You have only provided one site as an example - have you tried the others without scripting?

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Answer 6

jhros Author

Level 1

8 points

Mar 1, 2016 9:40 AM in response to Drew Reece

I'll try to be a little more specific about the problem. It seems to occur on many different websites, but maybe more often on tu.no than other pages. Two other examples are db.no and nettavisen.no.

When the scrolling issue first occur, it will not only affect the page I visit at that time, it will continue when I surf other pages as well. If I wait until a page is completely loaded, scrolling is still bad. So it seems that some pages will corrupt safari in a way that makes safari fail on most of the pages I visit after the problem first occurred. This scrolling issue will not disappear until I kill the safari app completely and reopen. The number of other active apps has nothing to say. Safari fails even if no other apps have been opened after the last restart of the ipad.

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Answer 7

jhros Author

Level 1

8 points

Mar 2, 2016 1:14 AM in response to Drew Reece

I will try for the next days with scripts enabled and disabled, and see if there is any difference. I'll give it a little time to see how things are going. Thanks a lot for all the time you've put into this!

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Answer 8

jhros Author

Level 1

8 points

Mar 6, 2016 9:05 AM in response to jhros

I have now tried for a while, turning off jacascript in safari when the scrolling issue appears. This helps immediately, so there is no doubt that JavaScript has something to do with it.

But I don't see this as a solution to the problem. Many pages depend on JavaScript to show correctly, and I have had some trouble watching videos with JavaScript turned off.

Apples newest and most expensive ipad should work right out of the box, not having to shut off important functionality to make it work. Since there are other ipads working fine without shutting off JavaScript, I suppose there could be something wrong with my ipad. I will therefore deliver it for service, and see what they say about it... I'll come back here with info when I have it back. Might take a while....

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Answer 9

Drew Reece

Level 6

10,684 points

Mar 6, 2016 3:17 PM in response to jhros

jhros wrote:

Apples newest and most expensive ipad should work right out of the box, not having to shut off important functionality to make it work. Since there are other ipads working fine without shutting off JavaScript, I suppose there could be something wrong with my ipad. I will therefore deliver it for service, and see what they say about it... I'll come back here with info when I have it back. Might take a while....

Make sure you pass on the problematic web addresses for testing. 'Postit note' them to the device so the testing engineer sees them 🙂

I suspect Apple will erase the device to test, take a backup in iTunes/ iCloud before you send it off & remove it from 'Find My …' in iCloud, you can also test after a factory reset, but I doubt it will help. My suspicion is that the sites have badly performing scripts. It is possible each device is seeing different scripts because some are loaded based on past browsing history (adverts can be specific to the sites & searches you have made for example). Clearing all history may alter the behaviour until more cookies & history is created.

There are probably other Safari extensions that may be able to disable scripts for certain sites, it isn't ideal but if a site is badly made it can cause issues like this. It is also difficult for the site developer to test since they may run different scripts or results based on their browsing history too.

You may find using the adblock browser is a way to view these sites in the meantime, whilst leaving scripting active in Safari.

https://adblockbrowser.org/

Have you contacted the sites in question?

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