I understand that you're using a free tier of our Atlassian Cloud service and want to know if you can install Marketplace add-ons to this site.
Yes it is still possible to install add-ons, even to the Free tier of Jira Cloud. However not all add-on vendors are required to support their add-ons on the Free tier. With the Free tier of Cloud there are some architectural differences and limitations, such as project permissions, issue permissions, anonymous access to projects, and more detailed in Jira Cloud plans: What do I get with each plan?
I also recommend Limitations in Jira Cloud Free plans. It contains a current list of known add-ons that will not work in the Free service level Jira Cloud sites.
In case you were asking this question because you were unable to do this yesterday, you should know there was an outage documented for a Marketplace site yesterday that might account for a temporary inability to see/install add-ons to any site. More details on that can be found in https://developer.status.atlassian.com/incidents/3x7vrj8p2j5x
I hope this helps.
Atlassian's marketplace partners have had a very productive start to 2021! Since our last roundup, our developer community has added over 160 new cloud apps to the Atlassian Marketplace to help you...
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