Bug#838734: [plasma-discover] plasma-discover uninstalls packages during upgrades without asking for confirmation

[Matthias Klumpp <matthias@tenstral.net>]

Discover is for end-users with no technical knowledge. Showing extra
dialog boxes with crazy text won't help and just be visual clitter,
since people will press "Yes" anyway. Also, Discover isn't really to
blame for the underlying problem, which is a busted archive, something
that never happens in any stable distribution.
However, it would be nice if Discover handled this situation better on
unstable development versions of a distro.

I see the following possible solutions:

1) Have Discover detect an unstable distribution, and if it finds one,
show an extra confirmation box if changes that cause the removal of a
package are detected.

2) Just display removals as seperate items in the updates list
unconditionally - people on unstable distros would just need to read
the information then.

3) Show a "This update is potentially disruptive if you are using an
unstable distribution" or any other meaningful message when big
changes are detected (e.g. > 10 packages being removed)

Since even on stable distros sometimes transitions happen and stuff
gets removed, adding an unconditional dialog seems like a bad idea,
simply because it's meaningless for average users.

I'll talk to the usability people about the different options, and
hopefully we can land one of them before Plasma 5.8 is released.

Cheers,
    Matthias