Martingale only works for very short term and if you have luck ,you will lose faster if you play at site which have bigger house edge
No strategy works neither for short or long term, if something worked for short term logically it would work for long term as well, unfortunately nothing works
For Shortterm there is a difference. If say a long losing streak of 20 rolls happens with a chance of 1 in a million , then if you use that stratgey only for 100 rolls, it is less likely to happen in the start and martingale might actually work out for you. But obviously there is a chance it happens in the start, but now if you roll only 100 bets, its much more chance it won't be within those 100 rolls.