Add the missing certificates to C:\Program Files\Git\mingw64\ssl\certs\ca-bundle.crt
. For exemple, Sectigo intermediate certificates can be obtained from here
Add the missing certificates to C:\Users\rocco\AppData\Local\Temp\insomnia_2021.6.0\ca-certs.pem
. Renew the operation with each update.
There is an open pull request that load certificates from Windows Store : Kong/insomnia#3203