Use this tool to remove invisible ChatGPT special characters, also referred to as "watermarks"

...which they, in fact, are not. ChatGPT is, like every other LLM, just a crappy piece of junk. But it can jiggle, so people are impressed. A dog fetching the newspaper is more impressive. Much more. It's not even close.

This tool finds 0xa0 and U+202f and replaces them with a space.

This tool seems not to be needed anymore, ChatGPT appearently does no longer use different type of spaces for its texts.
See here: https://www.rumidocs.com/newsroom/new-chatgpt-models-seem-to-leave-watermarks-on-text