Czech-language admin + diacritics support (č / š / ř / ž), what does that involve?

Magento has decent Czech locale (cs_CZ) support out-of-the-box but production-grade Czech needs polish:

• Admin locale, set per-user, falls back to en_US. We ship the official Crowdsourced cs_CZ translation pack + project-specific overrides (your store’s product attributes, custom modules, email templates).
• Storefront locale, full Czech UI strings (cart, checkout, customer account, search filters), Czech-language product attribute labels, Czech category names.
• Diacritics support, UTF-8 throughout (MySQL utf8mb4 collation, never latin2 or windows-1250). Search (OpenSearch / Elasticsearch) needs the Czech analyzer + stemmer for searches like “tričko” vs “tricko” to match.
• URL slugs, transliteration to ASCII (e.g., “dětské-obleceni” → “detske-obleceni”) for SEO-friendly URLs. Magento’s default URL-key generator handles this if configured correctly.
• Customer-service emails, Czech-language order-confirmation, shipping, refund templates. Czech address format (street name, house number, postcode, city, not English line-order).
• NUTS-3 region handling, if you do regional tax / shipping by Czech kraj (region), Magento needs the 14 CZ regions seeded in directory_country_region.