I use this Chrome extensions Grammarly which corrects my English typing and helps with it.

https://app.grammarly.com

Now the WYSIWYG editor goes a bit beserk when this is active. Copy/paste seems to chop all text in parts, Styling text seems horrible but i dont think that is because of this addon. When i turn it off, it still adds different styling randomly.

Are there known issues with these kind of extensions?