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Text → gives you the opportunity to let the user fill in the Metadata field with a simple text string.
Multi select ->→ gives the user the option to select several values from several pre-defined options coming from a dropdown menu.
Single select → gives the user the option to select one value from several pre-defined options coming from a dropdown menu.
Page link → you can draw connections, for example, to existing pages.
User (single/multi user) → allows you to select all available Atlassian users who have site access.
Date → allows users to select a date from the past or the future.
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