Sage CRM 2021 R2 will be the last version of Sage CRM tested with Internet Explorer. Support for Internet Explorer will therefore end from Sage CRM 2022 R1.
Sage CRM 2022 R1 will include a new version of the Outlook Integration to remove all dependency on Internet Explorer and ActiveX.
This applies for Sage CRM stand alone and when integrated with Sage accounting products. Sage 50, Sage 100, Sage 200, Sage 300, Sage X3 and Sage Intacct.
More information and references can be found here: https://www.sagecity.com/sage-global-solutions/sage-crm/f/sage-crm-announcements-news-and-alerts/170220/advisory-internet-explorer-will-not-be-supported-in-sage-crm-2022-r1-onwards