make a loop inside macro code, without using the loop button

could i make it a loop in code instead of using the loop button of imacro?

becoz the default looping button is 3 and i have to increase to 99999 every time,thats very time consuming, thanks in advance!

spec: MAC + firefox + imacro

SET !ERRORIGNORE YES
VERSION BUILD=8820413 RECORDER=FX
TAB T=1

URL GOTO=https://xxxss.com.xx
URL GOTO=javascript:window.scrollBy(0,300)
wait seconds=10
URL GOTO=javascript:window.scrollBy(0,830)
wait seconds=0.6