Steps to reproduce:

Go to http://ngs.musicbrainz.org/release/d8656bf1-eb85-4e7f-957c-b5bf81565e57/edit
Click Tracklist
Paste in track times from http://pastie.org/private/typohhka7tllttxixjiq
Remove the redundant 1 - 10 entries from top.
Click Edit Notes
-> waaaaaait

It seems to be loading up the "Add Missing entities" page that is very slow. Copy and pasting over the entire tracklist seems to require it to re-confirm every single artist?

Even after it has loaded the "add missing entities" page 1st time (which only requires confirmation of 5 artists), it's then very slow to go back and forth with the tracklist tab.

Although it seems there are some performance problems with determining missing entities in general - in this particular circumstance, does it really need to re-confirm all the artists since the text of them is the same before and after the tracklist was parsed? (it's only times that are different)