Starting from the 7.0 version, all extensions are included in the dhtmlxgantt.js file, so it is possible to have different extensions for several Gantt instances.
For example, enable auto-scheduling and tooltip only for the first Gantt instance and multiple task selection with the Quick Info only for the second Gantt instance: http://snippet.dhtmlx.com/5/469868442
So, if you have several Gantts on the page, now it is more convenient to customize them.
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