Comment 22 for bug 95854

Which is the trouble with this bug: it's actually several otherwise very minor shortcomings that add up to a nasty result.
Apples-to-apples check did fix one problem, but it's circumvented via another.

The second "big" deal, of course, is that usually symlinks are treated as their targets, but using this approach in ALL contexts indiscrimiately is bad.
But.
The dialog itself is flawed: it's important enough to show more than a tab does, and it shows less.
Icons are good, but why the usual overlaid emblems are NOT applied in confirmation dialog? Then symlink would be at least clearly marked as such.
Then, there's "Size:(null)" for directories. Sure, looking inside slows down the huge list - but in the dialog there's only one item and for merging/overwriting purpose it's kind of important what's inside it, so perhaps settings different from the file list (and more verbose by default, at least on "X files + Y directories" level, though seeing the size of at least of immediately contained files would help too) would improve the situation.

Speaking of dialog, overwriting a directory with file is already unusual enough that perhaps this should be a separate category for "apply to all" purpose - just to be on the safe side. Merging a newer directory into old may call for overwrite of old files, but this shouldn't easily lead to something so strange and drastic.