Beberapa hari menjelang lebaran disediakan makan sahur, tp harus siapa cepat dia dapat

Sangat dibolehkan walaupun hanya sekedar lihat2

Sangat bisa, Istiqlal merupakan masjid besar dan berbeda dari kebanyakan masjid yang umumnya terkunci di malam hari.

Open all day but miss prayer times if not praying

Hi Hello Elodie T, Don't worry, there are private storage / lockers available, and there is a guard, sure to be very safe. Best Regards & Friendship, Java Private Tour.

Sarong (man) and kaffetani (women) are available at the info point at the entrance. The mosque is viewable only with a guide, English speaking for a donation. Obviously not shoes . I think under the knees trouser is accettable.

No you don't need to come in a group you are always welcome during office hours but you must take of your shoes and someone will guide you around of the official employees and if you where a short they will give you something you can use to see the mosque.

If you take a tour, which you will most likely have to do, there is a small area to keep your shoes (which you need to take off at the very entrance to the mosque). If you are dressed inappropriately, they will give you a robe to cover up that you return when the tour is finished.