In previous versions, when applying a quick filter in the backlog view, the sum of all estimates shown in the top right corner would change to show the sum of only the visible issues:

Now, applying a quick filter does not change these numbers:

Based on your release notes, this change does not seem to have been intentional. The old behavior was very useful. For example, if I click a "My Work" filter, I could see at a glance how many points I have in my sprint.