This article explains how to uninstall Foxit PDF Editor Cloud in SharePoint.
1. Select Azure Active Directory under Azure Services
You can search Azure portal via http://portal.azure.com
2. Select Enterprise applications on the left menu bar
3. Select All applications → enter sharepoint → click Foxit PDF Editor for SharePoint and OneDrive
4. In properties, Click No for Enabled for user sign in
5. In Users and Groups, select the user account and click Remove
6. In properties, delete the App. Sign out and re-sign in.
Note that the uninstall procedure may take up to 48 hours and please don't use Foxit PDF Editor for SharePoint and OneDrive during the 48 hours, or it will cause uninstall failure.