A more elegant solution would be to use the alarm handling methods:
flashBorder | oldBorderColor | oldBorderColor := self borderColor. self borderColor: Color blue. self addAlarm: #borderColor: with: oldBorderColor after: 3000. "reset the border color after 3 seconds"
You only have to be careful not to call this method while the border color is set to blue - otherwise the change will be permanent...
Cheers, Hans-Martin