I noticed a new and odd behavior yesterday. All of a sudden, I can no longer preview plain text files if the extension is .txt (which is generally the case.) With other plain text files, such as .bat or .log (or with no extension at all), the preview behaves as expected. And here's a possible clue: when attempting to view the files, the status line above the preview window, which normally shows something like, "deploy.bat - 27 lines, 547 bytes, instead reads (for example), "readme.txt (Monaco)". It literally appends the word Monaco in parentheses after the file name. The preview window contains no error -- just a blank. I can rename the .txt file and it then previews. It seems something is affecting only files with that particular extension. (I searched to see if I had anything installed with Monaco in the name -- no such luck. In fact, I have not installed any new software recently.)
Any suggestions?