In that case (using your example) it looks like the attached. Both body and pre text are small, but about the same size.
If no one else is seeing this issue, then I probably need to change the browser for reading the GNU manual nodes. I am seeing this on the Android Chrome browser.
About not "top-posting", I had to google to understand what that meant :) I am replying from the Gmail app and this time I unchecked the "Quote text" checkbox which is always checked by default.. hope that helps this time.