New T Extension fields and subfields [Unicode Locale/Language Identifiers. These T extensions provide for the identification of transforms that can be used for tagging content or requesting resources. The new T extension fields and subfields are defined in the following files, as part of the CLDR 21.0.2 release:

i0-Input Method Transformations: bcp47/transform_ime.xmlk0-Keyboard Transformations: bcp47/transform_keyboard.xmlt0-Machine Translations: bcp47/transform_mt.xmlx0-Private Use fields: bcp47/transform_private_use.xmlFor example:

"zh-t-i0-pinyin", to indicate Chinese text generated with a pinyin input method"en-t-k0-dvorak", to identify a Dvorak keyboard for English"it-t-k0-osx-extended", to request an extended Mac keyboard for ItalianThe private use subfields can be used for private agreements, such as:

"ru-t-en-x0-mobile", to indicate a translation from English to Russian for use on a mobile device, or"ja-t-de-t0-und-x0-medical", to identify a machine translation from German to Japanese with a specialized dictionary for medical terms.

Related to this, there is draft keyboard layout data currently slated for CLDR 22.0: see Draft Keyboard Charts.