APPLE: Critical Bug in scroller style on El Capitan

Preferences -> General -> Show Scroll Bars -> "Automatically based on mouse or trackpad" means that the behavior depends on whether a mouse is connected or not. That means the scroll bars will look different in those two cases. (Presumably one of your Macs has a trackpad, the other only has a mouse.) So even with the default setting, you can't know which the typical user will see, because you don't know whether a typical user has a trackpad or not. It's not an El Capitan issue.

Note also that there are three possible appearances of a scroll bar: not visible at all, visible as a temporary overlay, and visible in a scroll track. The last of these can be persistent (when the user has a mouse) or temporary (when the user has a trackpad, but the mouse pointer is over the scroll track location and the scroller is visible).

That means there's no "correct" appearance for your screen shot on any version of OS X. I suggest you take screen shots with the scroller invisible, because that's the least cluttered. Your users will know how to recognize and use scrollers in whatever configuration appears on their own Macs.

See something - file something. Bug report link is below right.

Do that and see what comes back, etc.

Be sure to add your report # to your thread for ref.

A cosmetic bug is hardly serious.

A serious bug is one that renders the Mac unusable, even if only temporarily, e.g., a kernel panic.

>A cosmetic bug is hardly serious.

Said the pig, covered in mud...

When the user questions the UI, they question the application. When they question the application, they question the vendor. When they question the vendor, they start looking at other choices - for want of a nail... El Cap has many faults that when aggregated show it needs help and Apple needs to hear about them all - let the feedback system decide how to weigh their impact.

Thanks so much for the reply QuinceyMorryis!

Both Macs as MacBook Pros and both have only a trackpad - neither has a mouse attached.

The scrollbar does not disappear on ElCapitan. It stays visible whether or not the user is over the scroll track location and whether or not the scroller is visible.

With a default MacBook Pro, trackpad only, scrollbars are now permanently visible on El Capitan. They do not go away. The scrollbar and the scroll track are permanently visible with a trackpad on a Macbook Pro in El Capitan.

I need the scroller and scroller track to disappear when not scrolling, like they did in Yosemite. This is absolutely critical to the look and feel of my app. How can I restore this behavior to how it worked in Yosemite. It feels odd that this choice was taken away from me ... :-(

Thanks again for your help Quincey! I know you're busy and I appreciate you taking the time to help me.

>> With a default MacBook Pro, trackpad only, scrollbars are now permanently visible on El Capitan. They do not go away.

That certainly seems wrong, but it's not happening generally on El Capitan. (It certainly not happening to me.) Is there any chance you have a Bluetooth mouse somewhere nearby that's previously been paired with the MacBook? I think KMT's advice is good — file a bug report, it can do no harm.

Anyway, I still think the best approach is to take your screen shots without scrollers, for the other reasons I mentioned.

Hi Quincey,

Thanks again for responding.

The Macbooks in question have been connected to bluetooth Magic Mouse and (detached Apple) Trackpads in the past. But neither the mouse nor the trackpad are connected right now, in fact, neither even has batteries in them at the moment.

Why would the fact that a long time ago I attached a bluetooth mouse impact how the scrollbars appear now? Right now I'm using the trackpad built in to the Macbook, so shouldn't I get the behavior for a builtin trackpad?

If the scrollbars are being styled according to a bluetooth mouse that once was connected but is not currently connected, that definitely seems like a bug to me.

Thoughts?

You could try a visit to the Bluetooth pane in System Preferences. If the old devices are listed there as paired (they might be, even if they're not currently connected, you could try unpairing them).You could also try connecting a mouse, then disconnecting.

This sounds like one of those minor bugs where some setting got stranded in a preferences file, and there's no direct way to reset it.

Or, I hate to suggest the unsophisticated approach, but you could just take it an Apple store and pretend to be a civilian — "My scroll bars won't go away!", you can say innocently. It may be something they're used to seeing and resetting.