Extends a Class will make losing and corrupted types in a child class. · Issue #42541 · microsoft/TypeScript · GitHub

When we add types on properties base class, if a child class extends this base class, we will lost types and get corrupted behavior. Actually is seem affected by keyof T, i not tested all others types, but this one make coruptions. From

typesVersions should not be affected by `types: ` · Issue #28304 · microsoft/TypeScript · GitHub

Crash in compiler when using `extends null`, `super()`, and re-opening class with `interface` · Issue #55499 · microsoft/TypeScript · GitHub

Extends a Class will make losing and corrupted types in a child class. · Issue #42541 · microsoft/TypeScript · GitHub

Support final classes (non-subclassable) · Issue #8306 · microsoft/ TypeScript · GitHub