Same happening for me too, happens for both Internet hosted and Local model providers, all get cleared after restarting Xcode. Using: Xcode 26.2 (17C52) from App Store Tahoe 26.2 (Separate issue, but seems that from 26.2 the code snippets are also not showing properly for these models with format ```swift or ```text, they can just be copied, but not showing the preview)

Probably irrelevant anymore, but I used the guide How to use Google Gemini in Xcode 26 beta from Carlo Zottmann Notes: Watch out to add Bearer before API key No need to worry about Xcode adding /v1, Gemini API will handle that