Tea on shabbos
Is one able to use a kli shlishi to make tea on shabbos?
This is a matter of debate among poskim. The Mishna Brura requires tea sense be made before Shabbos, yet he himself mentions the leniency of kli shlishi in other places. Igros Moshe allowed kli shlishi. So if you don’t have an established custom or psak from your Rav, you should ideally avoid making tea in kli shlishi, and should prepare tea sense before Shabbos.