Userpics on old entries shouldn't change when I select a new "default"
Short, concise description of the idea
When I select a different userpic as my default, my old journal entries and comments should still display the userpic they had when they were posted, not the new default picture.
Full description of the idea
Say I have two user pictures: one has keyword 'good day' and the other has keyword 'bad day'. Say I'm psychopathic, and so the 'bad day' user picture is my default, and I post a bunch of depressing journal entries with it... but then one day I start taking Prozac, and I decide to change my default user picture to my 'good day' picture. This suddenly changes all of my old journal entries to use the 'good day' picture! Or: Say it's Christmastime and I upload a Christmas userpic and set it to the default. Now if someone goes back and reads my old journal entries and comments, the Christmas userpic shows up all over -- in my Thanksgiving entries, in my Halloween entries, and so forth. When I post a journal entry or a comment, what's probably happening is that the LJ code is noting down 'this entry uses the default userpic' -- and then of course the userpic associated with that entry will change if I later change my default. I feel that LJ should instead note down 'this entry uses the userpic with keyword "foo".' If a user really *does* want the userpic on all his old journal entries and comments to change, then all he needs to do is upload a new userpic and give it the keyword he used before, or exchange keywords between the userpic on the old entries and any other userpic. (Note that I'm not talking about LJ remembering userpics that a user doesn't currently have uploaded in his account; I know that would be much more complicated.)
An ordered list of benefits
An ordered list of problems/issues involved
An organized list, or a few short paragraphs detailing suggestions for implementation