Usually the Fixlet should describe the issue and give you more information where necessary. In this case of the “service recovery action”, we released this when we noticed that sometimes the MSI installer would not properly set the agent to restart if it was stopped unexpectedly. This Fixlet adds this setting if it doesn’t exist.
Yes. You can choose to subscribe to both of them if you want the updates.
For the second question: The Fixlets are designed to be self-documenting. We can update the description if the Fixlets are missing useful information, but we don’t maintain a separate documentation system for a Fixlet.