In Windows You should just copy-paste the text with formatting, select the copied part, click
Ctrl + Spacebarand formatting is gone. Unfortunately this does not remove hyperlinks or tables.
In Mac OS You should copy the text and paste it with hot keys
Cmd + Alt + Shift + Vand text is pasted without formatting. Unlike Windows combination this also removes hyperlinks and tables.
In both OS's these hot keys are working everywhere: in text editors, in browsers, in mail clients etc.