FrontEndRuntime

Wolfram Kernel

Execution environment

Notebook`Editor`Kernel`FrontEndRuntime`

Context

wljs-editor

Package

FrontEndRuntime[]

an interface to modify frontend runtime from Wolfram Kernel.

Append Javascript, CSS from WL package

It comes handy while developing Wolfram Language Packages together with Javascript modules and styles. To extend frontend runtime with external scripts or styles simply Append them

FrontEndRuntime[{"Modules", "js"}] = Append[FrontEndRuntime[{"Modules", "js"}], File["path to your JS"]]

FrontEndRuntime[{"Modules", "css"}] = Append[FrontEndRuntime[{"Modules", "css"}], File["path to your CSS"]]

These command automatically add the provided data to all opened notebooks and will keep them in the current session (even if you kill a Kernel or reload a notebook)

How to check if a Wolfram Package runs in WLJS Notebook environment

There is a special internal variable for this purpose available from any context (technically you specify the context explicitly)

Internal`Kernel`WLJSQ // TrueQ