LookdevX scene callbacks in Maya 2025

Product: Autodesk Maya 2025
Component: LookdevX
Version: ( Maya 2025.3.1)
OS: (Windows 11)

Summary

Severe performance slowdown when creating a new scene (File > New Scene) with the LookdevX plugin loaded.
The slowdown is caused by repeated global scans of materialxStack nodes during scene teardown.

Steps to Reproduce

Launch Maya 2025 (LookdevX plugin auto-loaded).

Open any scene with some geometry and materials.

Go to File > New Scene.

Observe that Maya hangs/freezes for several seconds.

Check Script Editor: it repeatedly calls

ls -type materialxStack -long

If the LookdevX plugin is unloaded before creating a new scene, the issue disappears.

Expected Result

Creating a new scene should be fast, regardless of whether LookdevX is loaded.
LookdevX should not perform unnecessary global node scans (ls -type materialxStack) on every scene switch.

Actual Result

With LookdevX loaded:

Maya freezes noticeably when creating a new scene if another scene is already open.

Script Editor shows repeated ls -type materialxStack -long calls.

With LookdevX unloaded:

Creating a new scene is instant, no slowdown.

Impact on Workflow

New/Open Scene operations are significantly slowed down in production environments.

This affects users who do not actively use MaterialX/LookdevX but still have the plugin auto-loaded.

Makes scene iteration painful in larger projects.

Workaround

Manually unloading LookdevX before creating a new scene:

import maya.cmds as cmds
if cmds.pluginInfo("lookdevX", query=True, loaded=True):
cmds.unloadPlugin("lookdevX")

This avoids the slowdown but prevents the use of LookdevX until reloaded.

Request

Please optimize LookdevX scene callbacks in Maya 2025 so that:

It does not repeatedly scan for materialxStack nodes on every scene switch, or

It only scans when MaterialX features are actively in use.

Reproduce the slowdown in Maya 2025.3.1 with LookdevX loaded by opening a scene and using File > New Scene, then inspect the Script Editor for repeated `ls -type materialxStack -long` calls. Trace the LookdevX scene-switch callbacks involved and verify that scene creation no longer freezes or performs unnecessary repeated global scans.

Written by the indexing model from the issue text.