Hello and welcome!
Are you referring to this app? https://marketplace.atlassian.com/apps/1214789/rich-filters-for-jira-dashboards?hosting=server&tab=reviews
It's a paid app only available for Server, not Cloud, as far as I can see. Since it looks as though you are asking about Jira Cloud, you won't be able to enable it.
Depending on your use case, you can look for alternative solutions in the Atlassian Marketplace.
If you're looking for a cloud app that enables you filter Jira dashboard gadgets dynamically, you can try our Jira cloud app Quick Filters for Jira Dashboards.
For JSM June Challenge #2, share how your non-technical teams like HR, legal, marketing, finance, and beyond started using Jira Service Management! Tell us: Did they ask to start using it or...
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