After I created the previous post, I updated the firmware to 20230913-114008 and it appears that Shelly has changed the operation of dim up and down URL Actions. They no longer repeat. So, you have to trigger the switch multiple times to ramp up/down.
Because of this, I rearranged my URL actions to the following:
BUTTON 1 LONG PRESS URL = http://localhost/light/0?turn=on
BUTTON 2 LONG PRESS URL = http://localhost/light/0?turn=off
BUTTON 1 SHORT PRESS URL = http://localhost/light/0?dim=up&step=10
BUTTON 2 SHORT PRESS URL = http://localhost/light/0?dim=down&step=10
And, I removed the switched off actions.