When you install VSCode you can see that the last two lines are:
Configuring sandbox profiles...
Sandbox profiles updated!
From Parrot 3.9 there is the sandbox feature using firejail. This system creates a profile file under /etc/firejail for every installation. The file contains rules to protect your application, such as Networking rules.
As you can see in the documentation:
–net=none creates a network namespace unconnected to the real network. The sandbox looks like a computer without any network interfaces.
So you have to comment (or delete) in /etc/firejail/code.profile the line
net none
Your VSCode will load the extensions list now! (I had the same problem)
EDIT:
Pay attention to updates, because the Firejail profile files are overwritten, as you can see in the profile file:
# This file is overwritten after every install/update
If you update/upgrade your system for example, check something like this:
Configuration file '/etc/firejail/code.profile'
==> Modified (by you or by a script) since installation.
==> Package distributor has shipped an updated version.
What would you like to do about it ? Your options are:
Y or I : install the package maintainer's version
N or O : keep your currently-installed version
D : show the differences between the versions
Z : start a shell to examine the situation
The default action is to keep your current version.
*** code.profile (Y/I/N/O/D/Z) [default=N] ?