Follow the below steps to find out if you are using List Component with SharePoint Online.
Locate Solution Gallery in SharePoint:
If you are using Microsoft SharePoint 2010: Click Site Actions, then Site Settings, and then under Galleries, click Solutions.
If you are using Microsoft SharePoint 2013 or SharePoint Online: Click the Settings button in the top-right corner, then Site Settings, and then under Web Designer Galleries, click Solutions.
This is where the list component will be present, if installed already.
Before you move to Server based SharePoint Integration, we recommend that you review the Important considerations for Server based Integration article to take any necessary actions for your current solutions.
You can follow this article in order to start the migration process to Server Based Integration from the List Component. In the same article, scroll down to the end to view the “See Also” section and click on the article link that best defines your SharePoint and CRM setup in order to complete the migration.
Feel free to contact us us if you would like us to assist you with the migration process.