Simple iMacros script crashing Firefox all the time

iMacros: 9.0.3
Firefox: 49.0.1

I start the script and it always crashes after a little while. I first thought it was due to a RAM leak as FF usually crashes after around 1000 iMacro loops. However sometimes FF crashes after just ~10 iMacro loops and the RAM is never even close to getting ful. Got 10 GB RAM. Win 7.

I'm stuck, I have no idea how to solve this problem. It's nothing wrong with the script:

VERSION BUILD=9030808 RECORDER=FX
SET !ERRORIGNORE YES
SET !LOOP 999
TAB T=1
URL GOTO=addmefast,com/free_points/twitter_retweets?c=f35290358
TAG POS=1 TYPE=DIV ATTR=TXT:Retweet
WAIT SECONDS=3
TAG POS=1 TYPE=INPUT:SUBMIT FORM=ID:retweet_btn_form ATTR=NAME:commit
WAIT SECONDS=3
TAB CLOSE
TAB T=1
TAB T=1
URL GOTO=addmefast,com/free_points/twitter_favorites?c=f35290358
TAG POS=1 TYPE=DIV ATTR=TXT:Favorite
WAIT SECONDS=3
TAG POS=1 TYPE=INPUT:SUBMIT FORM=ID:favorite_btn_form ATTR=NAME:commit
WAIT SECONDS=3
TAB CLOSE
TAB T=1

Can someone pleased help me here?

Try reinstalling your firefox ? Firefox really sucks.

It's not just you I'm having the same problem with iMacros. It just keeps crashing. I think they're trying to switch over to a paid service as they keep prompting me to register my email. So I'm not really sure what's going on with this company.