Bug 298260 – Safari 26 reports iOS 26 version as 18.6

• Status: RESOLVED
• Resolution: WONTFIX
• Component: New Bugs

Running the iOS 26 beta, I noticed the iOS version reported in the useragent is 18.6.

"Mozilla/5.0 (iPhone; CPU iPhone OS 18_6 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/26.0 Mobile/15E148 Safari/604.1"

Steps to Reproduce:
1. Install the iOS 26 beta.
2. Open Safari and navigate to a webpage that will show your useragent.

Expected to see "iPhone OS 26_0 like Mac OS X" as part of the useragent.
Actually see "iPhone OS 18_6 like Mac OS X".

Chrome on iOS reports the OS version accurately as "iPhone OS 26_0_0 like Mac OS X".

[Karl Dubost]

@zweglarz Which domain were you trying to access?

[Karl Dubost]

Ah no realized what you were talking about 

Safari is reported as Version/26.0
The OS is being reported as OS 18_6 *on purpose*. 
The OS version is being currently frozen.

(In reply to Karl Dubost from comment #2)
> Ah no realized what you were talking about 
> 
> Safari is reported as Version/26.0
> The OS is being reported as OS 18_6 *on purpose*. 
> The OS version is being currently frozen.

Thanks for the response Karl. When you say it is "currently frozen", does that mean it's going to say frozen when iOS 26 releases? Or are there plans to lift the freeze?

[Radar WebKit Bug Importer]

<rdar://problem/159767147>

[Brent Fulgham]

(In reply to zweglarz from comment #3)
> (In reply to Karl Dubost from comment #2)
> > Ah no realized what you were talking about 
> > 
> > Safari is reported as Version/26.0
> > The OS is being reported as OS 18_6 *on purpose*. 
> > The OS version is being currently frozen.
> 
> Thanks for the response Karl. When you say it is "currently frozen", does
> that mean it's going to say frozen when iOS 26 releases? Or are there plans
> to lift the freeze?

Our plan is to hold the OS release constant forever. We have encountered too many cases where website break or block access with OS version number updates. We have been doing this on macOS for years (for the same reason).

Safari version is a good analog for OS version on iOS, which should allow sites to conditionalize code (though it's best if they feature detect for that purpose).

[Brent Fulgham]

Please also note that the UA version information reported in Safari is controlled by the app (as is the case with all WebKit clients). Bugzilla isn't really the right place to file bugs about this behavior, as it is controlled by the Safari team (which are not the same people as the WebKit team! :-) )

[Brent Fulgham]

I'm mistaken! The version freeze was done outside of WebKit, but should have been done in the Quirk logic. I have filed Bug 298473 to address that (and move the logic into WebKit).

[Alexey Proskuryakov]

*** Bug 298717 has been marked as a duplicate of this bug. ***

[Colin Gourlay]

I've just downloaded the Xcode 26.1 Beta, and iOS 26.1 Simulators are reporting a new frozen version: 18_7. Are your respective teams able to keep in sync?

[Brent Fulgham]

All Apple platforms will soon be aligned to report version 18_7, which should not change in the future.  There may be another few weeks of syncing before this is true for every aligned platform.

[Colin Gourlay]

Great news! Thanks Brent