What is ctfmon.exe?
Ctfmon is a part of Microsoft Office. From the Microsoft Knowledgebase:
“What Is the Ctfmon.exe (Ctfmon.exe) File?
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Ctfmon.exe activates the Alternative User Input Text Input Processor
(TIP) and the Microsoft Office Language Bar.
What Does the Ctfmon.exe File Do?
Ctfmon.exe monitors the active windows and provides text input service
support for speech recognition, handwriting recognition, keyboard, translation,
and other alternative user input technologies.“
You can read the entire knowledgebase article, which includes instructions
on disabling Ctfmon: What Is CTFMON and What Does It