Type: LanguageService
I was recently exposed to an IDE which displays the size of a type (also structs and classes) or variable when hovering over the semantic object. So basically it just shows the number sizeof(type) would give you. It proved to be very handy when optimizing for memory usage and working with bit fields.

Here is a simple mock-up I made:

I was originally trying to implement such a feature as a standalone extension but came to the conclusion that this would probably need to be included into cpptools itself.

Also thank you for working on this awesome extension!