It's been a long time since I complained that we have to update subjects blindly without being able to see the details of what will change before pressing the fateful button, as it exists in the plugins, which you can always see what changes before deciding whether to update or not.
In addition, it is especially relevant to know what changes in a topic before updating, have active child theme or not .
But fortunately the good of ThemeZee has taken the witness and created a plugin, WP Theme Changelogs which adds precisely this functionality, so that we can update topics knowing what will change .
Once active the plugin there is nothing else to do. If the author of the topic keeps track of the changes as recommended in WordPress.org then you will see a new link next to the topic on the updates page, to see the details of the update.  If you click on it you will see the change log, the changelog of the subject, being able to make an update knowing what will change.
And, as I said, the only prerequisite is that the author of the topic has a section Changelog in the file readme.txt of his subject.
Come on, it is already integrated into the WordPress kernel and to be mandatory for the developers of topics to include the record of changes, do not you think?