Mac's Terminal comes with a default
PROMPT_COMMAND that checks the history and updates the current working directory (title of the tab):
echo $PROMPT_COMMAND to the top of your
.bash_profile and you'll see:
I want to add my own
PROMPT_COMMAND without over-writing the default. The default should come before my custom
PROMPT_COMMAND with a semicolon and space to separate the two.
Note that some programs (such as IntelliJ and VS Code) don't have a default! So I wouldn't want to include the space/semicolon in that case.