Intellisense wont show members in class

Multi tool use
Intellisense wont show members in class
Hello I have a really annoying problem.
Usually IntelliSense should show the members of a class i made for example:
However this only seems to work outside of classes.
if i try the same thing inside a Class it only shows members that i already
used in this class:
I've already tried this
this.rectangle = /**@type {Rectangle} */(new Rectangle());
but it still does not work.
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