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

Mixin base requires explicit type in TS 4.3 due to recursively referencing itself when it doesn't · Issue #44284 · microsoft/TypeScript · GitHub

Mixin base requires explicit type in TS 4.3 due to recursively referencing itself when it doesn't · Issue #44284 · microsoft/TypeScript · GitHub

class MyArray extends Array broken in Typescript 2.1.5 · Issue #13720 · microsoft/TypeScript · GitHub

Incorrect transpiled constructor of derived classes · Issue #12123 · microsoft/TypeScript · GitHub

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

Module not found when extending a class otherwise same code without extending no error · Issue #51260 · microsoft/TypeScript · GitHub

Mixin base requires explicit type in TS 4.3 due to recursively referencing itself when it doesn't · Issue #44284 · microsoft/TypeScript · GitHub