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The visible checkbox can be used (either manually or by using a display action). Variables which don't have this setting checked, won't be shown in any input form
The display filter can be used in combination with a filter in the Input Form Panel's properties. In that case, only variables with a matching filter will be shown inside the relevant panel. Multiple Panels can be configured, to show different sets of variables
Locked (New in 6.5 / 2021.1)
Locking the variable, will show a read-only version in the input panel, for end users of the Editor.
The variable is still accessible / editable through the API.
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For more information on display filters, see Conditional Interface Elements
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