Following the announcement of Google+ API deprecation
scheduled for March 2019, a number of changes will be made to Blogger’s
Google+ integration on 4 February 2019.
Google+ widgets: Support for the “+1 Button”, “Google+ Followers” and
“Google+ Badge” widgets in Layout will no longer be available. All
instances of these widgets will be removed from your blog.
+1 buttons: The +1/G+ buttons and Google+ share links below blog posts and in the navigation bar will be removed.
Please note that if you have a custom template that includes Google+
features, you may need to update your template. Please contact your
template supplier for advice.
Google+ Comments: Support for Google+ comments will be turned down, and
all blogs using Google+ comments will be reverted back to using Blogger
comments. Unfortunately, comments posted as Google+ comments cannot be
migrated to Blogger and will no longer appear on your blog.