Currently, the Web Client does not keep all completed subscriptions data like in the Desktop Client but you can control how long completed applications data should be present in the Monitor view on the Web Client by the configuration in webui.properties file. See these KDs TEC1555878 TEC1957845
By modifying the configuration, you can create a view for completed applications or search by application name, but making this configuration change not to clear completed subscriptions data will impact the Rest server performance.
Hope this helps.
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