Bold in Rich Text widget causes odd spacing before bolded word & undo turns whole widget bold

Dave shared this problem 4 years ago

As the following GIF animation shows, setting a word to bold in a rich text widget causes a huge space to appear before the bolded word when the widget is deselected (that is, when it loses focus and reverts to "display" rather than "edit" mode).

As also shown in the GIF, using "undo" causes all of the text in the rich text widget to become bold.