[Permagate]

People can sue you for insulting religion, there is a law for it (not specific to Islam, but religion in general). 99% of the times, this is a non-issue. People just don't care enough to bring the issue to court. However, if politic is involved, this can be used as a ground to discredit a politician. It is a hot topic this year before our capital's election, where one of the frontrunners was sued for allegedly insulting al-qur'an[1]

One other exception is if you live in Aceh. It is a special region in Indonesia which implements Islamic law to the tee.

[1] https://en.wikipedia.org/wiki/November_2016_Jakarta_protests