We’re removing instance names from MyDomain URLs for sandboxes. The instance name identifies
where your Salesforce sandbox org is hosted. Removing the instance name makes the URL cleaner and
easier for users to remember, for example, MyDomain–SandboxName.my.salesforce.com replaces
MyDomain–SandboxName.cs5.my.salesforce.com. This critical update was first made available in
Summer ’18.
https://help.salesforce.com/s/articleView?id=release-notes.rn_security_domains_stabilize_mydomain_cruc.htm&release=224&type=5

Assign users a single permission set group instead of multiple permission sets. Permission set groups
combine selected permission sets to provide all the permissions that users need for their roles. Remove
individual permissions from a group with the muting permission set feature to ensure that permissions
do not exceed user roles. Permission set groups were introduced as a pilot feature in the Salesforce
Spring ‘19 release. This beta release includes a new user interface for creating and managing permission
set groups.
https://help.salesforce.com/s/articleView?id=release-notes.rn_forcecom_psg.htm&release=222&type=5

Not only can you encrypt more data with Shield Platform Encryption, but you can manage your
encrypted data and settings more efficiently. Encrypt insurance fields and sync data to all fields and files
using the background encryption service. Enable Shield Platform Encryption settings in your scratch orgs
right from Metadata API. Get better filtering results on encrypted data with skinny table support for
deterministic encryption (generally available).
https://help.salesforce.com/s/articleView?id=release-notes.rn_security_pe.htm&release=222&type=5

Keeping a close eye on what’s happening in your org is easier with the new Real-Time Event Monitoring
feature, which is now generally available. Want to store the event data so that you can examine it in
more detail later? You now have six months to do it. With Enhanced Transaction Security, you can create
actions that trigger for any standard or custom object. We recommend that you start creating these
enhanced policies right away because we are retiring the legacy transaction security framework in the
future. Use the new Apex interface for asynchronous coding in your policies.
https://help.salesforce.com/s/articleView?id=release-notes.rn_security_em.htm&release=226&type=5

We’re moving customers with My Domains and Custom Domains to Salesforce Edge. The Domains
Setup page now shows more details, and new session-security-level policies control access to certain
Setup pages and objects. TLS 1.2 is required for all HTTPS connections, and instance names are
scheduled to be removed from My Domain sandbox URLs
https://help.salesforce.com/s/articleView?id=release-notes.rn_security_other_changes.htm&release=222&type=5

We’re accelerating domain requests for My Domains. With this update, you keep the same My Domain
address, but requests go through Salesforce Edge. Salesforce Edge uses machine-learning technology to
improve connectivity and performance. You can acknowledge this update to let Salesforce move your
org’s My Domain to the new service before the July 2020 auto-activation date.
https://help.salesforce.com/s/articleView?id=release-notes.rn_security_route_edge_my_domain_cruc.htm&release=224&type=5

Behind the scenes, we’re accelerating requests for Custom Domains by moving them to Salesforce Edge.
This move improves performance through machine learning. You don’t need to do anything for this
move. Keep using the same Custom Domain addresses for your Sites and Communities, and we’ll do the
rest.
https://help.salesforce.com/s/articleView?id=release-notes.rn_security_route_my_domain_edge_cruc.htm&release=226&type=5