Syntax highlighting is provided for Changelog and Locale files with Textmate grammar, and snippets are provided for many common patterns.
The fmtk lsp language server provides support for changelog files, including document outline and syntax validation.
The fmtk lsp language server provides support for locale files, including document outline and syntax validation.
In addition, locale keys are provided as completion items when typing strings in Lua, and "Go To Definition" is supported on locale key strings in Lua.