This exact kind of code worked at least a week ago (maybe even earlier yesterday), and then last night when I was working on some changes I noticed a new crash that was not happening within my code.

I'm not sure what would have caused this as I don't think my Matter devices had any firmware updates, nor the Flic Hub LR getting a firmware update.

It appears that the attribute is getting set, but something after that point in underlying Flic code is not expecting a Success value.

EXAMPLE CODE:

const matterModule = require('matter')
const matterDevices = matterModule.getNodes()

const matterDeviceIDsForNames = {}
for (const thisMatterDevice of matterDevices) {
	matterDeviceIDsForNames[thisMatterDevice.name] = thisMatterDevice.nodeId
}

const thisMatterDeviceID = matterDeviceIDsForNames['Living Room Corner Lamp']

const brightnessPercentage = 80
const brightnessLevel = Math.round(254 * (brightnessPercentage / 100))

matterModule.writeAttribute(thisMatterDeviceID, 1, 'Level Control', 'OnLevel', brightnessLevel, () => {})

ERROR OUTPUT:

SyntaxError: unexpected token: 'Success'
    at <input>:1
    at parse (native)
    at handlePacket (core.js:3259)
    at onPipeData (core.js:3336)