Based on the 3ds Max Slate Editor, this MME lets you edit several materials on one canvas. With it you can add/search for nodes, create node groups or ungroup them, copy/paste nodes individually or in groups (with wire connection intact), edit elements inside of a group, change wire style, create frames or delete them, create tabs, etc.

I created this to help me with large scenes with many materials. Rather than change them one at a time based on a single selected object I can select several objects, edit there materials en masse, and share nodes between them easily.

Nodes Browser
Create multiple tabs to organize your materials
Load selected objects materials
Auto-layout or snap to grid
Collapse/Expands nodes
Mini-Map
Search for used nodes
Create or Delete Groups
Enter and modify groups
Create or Delete frames and change their color
Wire styles and easy connect/disconnect
F1 Help Menu
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