How do I obtain update information that I can use to determine if I really need the update?

I am not a corporate IT department nor a deep system developer, but just an individual using Ubuntu on my home Lenovo Thinkpad Intel Core !5 laptop. After the recent (Jan /10/2018) Unity/Mesa issues with updating my 16.04 xenial system, I am gun-shy. I need a source of information that describes, in user/administrator terms, what a particular update is supposed to do or fix. After many days of scanning questions all over the various Ubuntu support sites, I finally have a development version of Mesa installed in order to make my system usable. I would like to get back to the pure LTS version as soon as possible. Yet, I can't tell if the latest set of updates in Software Updater addresses Mesa or not. Or, indeed, if it will remove the development version's change that made Unity's program launcher work for me again.

The descriptions in individual items in "Details of updates" seem to assume more knowledge of the underlying software libraries and kernel modules than I possess or need for my everyday use. Specifically, I would like the Software Updater to supply an overall description of what a particular set of updates (e.g. Security, Other, etc) is intended to address. IMO, expanding the "Details of updates" headers (Security Updates, etc) to have their own "Technical description" containing this information would be ideal. Therefore, I respectfully submit this idea for consideration. That is, unless there is some other channel from which this information could be obtained, without requiring days of discovery to locate. Even so, I think a link to it in Software Updater would be most helpful.