Temporary breakpoints (breakpoints that disappear once the method is complete) have been removed as of 4D v13. However, the debugger now offers a contextual menu with an option to "Run to Cursor" which is similar to the idea of using a temporary breakpoint. "Run to Cursor" will execute all code between program counter (the yellow arrow) up till the selected line where the cursor is. To get the below contextual menu in the debugger, simply right click in the pane that displays the code being executed.