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How much have Potlatch 1 and amf_controller been used
How many of the uses were undeletes?
What is the recommended alternative when browser Flash isn’t
I can't answer the general question, but where I tend to use
Potlatch 1 is when I quickly want to:
Quickly restore an object to a previous version of my choice
See what has been deleted in an area over time
It's possible to do (1) with the perl revert scripts. I don't
believe it's as straightforward (to "a previous version of my
choice") with JOSM, though if you're prepared to spend time with
partial reverts you should be able to achieve the same thing.
With the perl scripts you actually have more choice up front about
how you handle dependencies; with JOSM you get more chance to do
it interactively - neither of these approaches is right or wrong;
each is relevant at different times.
If I want to do what what you might call a "simple object
undelete" then JOSM's the best place to start anyway. For "simple
changeset revert" it may be too; the exceptions being if you want
to revert a lot of changesets or expect to have to do a lot of
reconciliation, in which case JOSM's interactive approach is
unlikely to be ideal.