Help "install package" is empty with VS version after reinstall all

because i've many problem recently with the last version of TMS Web Core VS, I decided to remove all install and start from new install (visual studio + tms extension). I have always a problem I can't swith from ide to design mode, I found that library was not installed. When I use "install package" i have no package, why ? yet myproject can compile and execute !! ??!!
Please help

Can you please post Visual Studio Code related questions in

Inspect via TMS Install Packages if the TMS WEB Core core package is installed (listed and checked). If not, browse and add webcore.twcl