[TxMt] Recovering from a screwed up find history list

[Dave Baldwin]

I inadvertently pasted several megabytes of characters into the find  
field of the search and replace dialogue box.  The performance of TM  
dropped significantly whenever the dialogue was displayed as a result.

I tried using the CLI tool defaults to remove the find history from  
the preference file and even reverted to an earlier version of the  
preference file (courtesy of Time Machine) to reduce the preference  
file size from 4.5M to 25K.  Unfortunately starting TM again somehow  
restored the preference file so I was still left with the problem.

It turned out the fix was simple - just select a few characters and  
Command E to make them the new find string.  Repeat with a different  
set of characters a dozen or so times.  This pushes the offending  
search string down the history list until it is discarded.

Dave.