how can we add the Dff in redwood pages using VBS

Summary:

for me i need to add a combobox in create work order confirmation ui in procurement which has been developed using Redwood UI ,

I have created a workspace using edit using visual builder studio in SaaS application.

in for some page i found there is no extensible components found what is the reason for that and how can i add a flex field in Redwood Pages,

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