Editing text on the boundary of a style change: bold, italic, hyperlink etc

Sometimes you want to add some text to the beginning of styled text—such as a web link—but when you try to do it, the text picks of the style from the text before your cursor. I work around this by putting the cursor between the first and second characters, typing what I want plus the first letter again, then going back and deleting the original first letter from the beginning of the text.

This also works for the end of text. Just put the cursor between the penultimate and last characters.