improve update review
@matthiasc
Submitted by Matthias Clasen Link to original bug (#715171)
Description
We currently notify and offer to review the just-installed offline update. The implementation is based on the presence / removal of a certain file, and is somewhat fragile. It would be nicer to have this backed by a database of past offline updates. Once we have that, we can also offer to review past offline updates, beyond just the most recent one.