I have next message in Komodo 11 and the whole php is replaced by [NUL][NUL][NUL] …
The file C:\xampp\htdocs\spreadsheetPDF.php could cause performance problems when viewed as language PHP, and is being treated as a plain text file instead. Possible reasons include large file size, long line lengths, and/or too many lines.
The msg you received just turns off syntax highlighting and other services to help with performance with massive files. Most editors do the same thing. The fact that the contents of the file is [NUL][NUL][NUL] tells me that the files isn’t actually txt. Is it possible that it’s a binary file?