When searching for a regular expression, and replacing with a blank string, both
"Replace" and "Replace All" recursively replace the search string.  If you enter
any replacement text, it appears to work properly, but replacing with a blank
string results in the incorrect behavior.

For example, enter a couple of lines with repeating "a" characters, then do a
regular expression search for "^aa", leaving the "Replace With" box blank.  When
you do a "Replace" or "Replace All", it will correctly remove the first two "a"
characters from the line, but then it will check that same line again and remove
the next two; it will repeat this until there are less than two "a" characters
at the beginning of the line, and only then will it move to the next line.  If
you enter anything in the "Replace With" box, even if you enter "aa", it will
correctly only replace once then move on to the next line.