Migration 2.0->4.0 documentation/plan?

Are there any documents/migration plans on moving from 2.0 to 4.0??? I’d like to know what I’m in for when we try to upgrade from 2.0 to 4.0

You can check the next documents

2x -> 3x
docs.dhtmlx.com/3.6/doku.php?id= … ersion_3.0

3x -> 4x
docs.dhtmlx.com/migration__index.html

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