I was reviewing a confluence page which was reviewed my many stakeholders. Something bugged me to an excruciating extent about the content of the page: something was off at some parts of the text. I inspected the page and it turns out the font color somehow changed to a mildly grayer color than black. This was likely due to a copy-and-paste that has gone wrong.
This problem has been haunting me for years, except in Google Docs. At some point, some template my team used had slightly gray text, and I STILL find it cropping up in our most recent documents.