Invoke like this:

const bb = require('window-blurbehind');
bb.DwmEnableBlurBehindWindow(myWindow, shouldEnable);

Where the first parameter can either be an Electron BrowserWindow or a window handle stored as Buffer.

shouldEnable is a boolean indicating whether the blur behind is to be turned on or off.

For best user and developer experience, do not set transparent to true. It has many shortcomings, such as no support for maximised window state and shadows. Instead set backgroundColor to #00000000.