fix typo: sync against apple naming convention

[PassionPenguin]

1/ System Preferences renamed to System Settings in Ventura
2/ unified OSX, OS X, Mac OS and macOS names accordingly
3/ XCode -> Xcode

notes that:

1/ FF relnotes are kept untouched (since the last occurrence of Mac OS or related strings in these files are FF48, at the time it was OS X 10.12)
2/ one occurrence is kept there based on what the description above said:

## macOS

Here, _x.y_ is the version of macOS (for instance, macOS 10.15). Starting in Firefox 87, Firefox caps the reported macOS version number to 10.15, so macOS 11.0 Big Sur and later will be reported as "10.15" in the User-Agent string. ARM-based Macs will be reported as "Intel" in the User-Agent string.

| Mac OS X version                    | Gecko user agent string                                                            |
| ----------------------------------- | ---------------------------------------------------------------------------------- |
| Mac OS X on x86, x86_64, or aarch64 | Mozilla/5.0 (Macintosh; Intel Mac OS X _x.y_; rv:10.0) Gecko/20100101 Firefox/10.0 |
| Mac OS X on PowerPC                 | Mozilla/5.0 (Macintosh; PPC Mac OS X _x.y_; rv:10.0) Gecko/20100101 Firefox/10.0   |

[github-actions]

Preview URLs (10 pages)

• /en-US/docs/Learn_web_development/Extensions/Forms/HTML_forms_in_legacy_browsers
• /en-US/docs/Learn_web_development/Extensions/Testing/Testing_strategies
• /en-US/docs/Mozilla/Firefox/Releases/18
• /en-US/docs/Web/API/Document/activeElement
• /en-US/docs/Web/API/Media_Source_Extensions_API/Transcoding_assets_for_MSE
• /en-US/docs/Web/CSS/@media/prefers-reduced-motion
• /en-US/docs/Web/CSS/@media/prefers-reduced-transparency
• /en-US/docs/Web/Media/Guides/Audio_and_video_delivery/Setting_up_adaptive_streaming_media_sources
• /en-US/docs/Web/Media/Guides/Audio_and_video_delivery
• /en-US/docs/WebAssembly/Guides/Concepts

Flaws (3)

Note! 9 documents with no flaws that don't need to be listed. 🎉

URL: /en-US/docs/Learn_web_development/Extensions/Forms/HTML_forms_in_legacy_browsers
Title: HTML forms in legacy browsers
Flaw count: 3

• unknown:
  • No generic content config found
  • no blog root
  • no blog root

External URLs (7)

URL: /en-US/docs/Learn_web_development/Extensions/Testing/Testing_strategies
Title: Strategies for carrying out testing

• https://developer.apple.com/xcode/ (1 time) (Note! This may be a new URL 👀)
• https://help.apple.com/simulator/mac/current/ (1 time) (Note! This may be a new URL 👀)

---

URL: /en-US/docs/Mozilla/Firefox/Releases/18
Title: Firefox 18 for developers

• https://bugzil.la/696045 (1 time) (Note! This may be a new URL 👀)

---

URL: /en-US/docs/Web/API/Media_Source_Extensions_API/Transcoding_assets_for_MSE
Title: Transcoding assets for Media Source Extensions

• https://brew.sh/ (1 time) (Note! This may be a new URL 👀)
• https://ffmpeg.org/ (1 time) (Note! This may be a new URL 👀)
• https://ffmpeg.org/download.html (1 time) (Note! This may be a new URL 👀)

---

URL: /en-US/docs/Web/Media/Guides/Audio_and_video_delivery/Setting_up_adaptive_streaming_media_sources
Title: Setting up adaptive streaming media sources

• https://caniuse.com/?search=hls (1 time) (Note! This may be a new URL 👀)

[pepelsbey]

I'm not 100% sure where it's supposed to be OS X and where macOS. Is there a difference worth keeping? I would rather make it consistently macOS everywhere, apart from historical references.

[PassionPenguin]

I'm not 100% sure where it's supposed to be OS X and where macOS. Is there a difference worth keeping? I would rather make it consistently macOS everywhere, apart from historical references.

1. several occurrences are kept in user agent strings. UA are still using Mac OS X (though incorrect since they are capped at 10.15). e.g. on Tahoe, Chromium reports Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36 Edg/141.0.0.0
2. Firefox release notes are untouched, as is described in the description of the PR. IMO these versions are built for Mac OS X, and they may use features deprecated in later macOS release. In addition, Apple themselves reference these versions as Mac OS X even today (see Mac OS X Mountain Lion Installer on March 08, 2024), so I'm not very clear if it's good to do a replacement in such cases

[pepelsbey]

I think it's a big consistency improvement. Thanks!