A friend of mine started getting some weird bug not so long ago.
Within the Find dialog text boxes at some point stop rendering carets and stop responding visually to keyboard input.
But every time you click the “Find” button content within those text boxes magically updates.
The only way to fix this is to restart TextMate. Closing/reopening Find dialog doesn’t help.
He made a video that shows this behavior https://www.dropbox.com/s/0hkhkrcqtzyi6ho/tm.search.bug.mov?dl=0
OS X 10.9
TextMate version 2.0-beta.6.8