Starting with the upcoming version of Windows 10 (October 2018 Update build 1809), Microsoft will stop releasing language packs in CAB format.
As you may know, since Windows 10 build 1803, which is the latest "firm" version of the operating system, Microsoft has released the Local Experience Packs or LXP language packs. The Local Experience Packs came as AppX packages and are distributed through the Microsoft Store.
The packages allow users to have various Windows functions such as Start Menu, Settings, and File Explorer in the language of their choice. In the upcoming Windows 10 build 1809 operating system, these files will replace the classic CAB file format used by language packs.
Starting with the next major release of Windows 10, we will only support language packs as Local Experience Packs. There will be no more .cab files for language packs. Local Experience Packs install faster and have a smaller footprint in the operating system (OS).