I'm looking for an extension that would reflect in 0.1 milliseconds to the read list

[Taifun]

The package manager extension returns the result as fast as possible..

Alternatively try

• PkgUtils Extension by vknow360, some tools to work with Package

• Get Apps Extension by Jinx (500 INR) to get all installed package names without QUERY_ALL_PACKAGES permission

taken from App Inventor Extensions | Pura Vida Apps

Taifun