Hello Karl,
If you mean the duration or time control in the lightbox, there are no built-in ways to do that. They are lightbox sections and Gantt adds event handlers to process the changes. So, if you just copy the HTML elements and add them to the modal, you will be able to select the date, but the duration and end date parts won’t be updated.
Here is an example: https://snippet.dhtmlx.com/3y6xdnwx
There are no public methods for these controls, so, if you want to reuse them somewhere in your application, you need to manually add the handlers.
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