Is the Istikhara supplication to be recited before or after the Taslim, and is it permissible to combine the two?

Scholars have differed on the timing of the Istikhara supplication. Some have favored supplicating before the Taslim (salutation of peace), while others have preferred doing so after it. Sheikh al-Islam Ibn Taymiyyah held that it is permissible to supplicate both before and after the Taslim, considering supplication before the Taslim to be better. However, the majority of scholars believe that supplicating after the Taslim is better, and this is the view favored by Sheikh Al-Uthaymeen, who based his argument on the Prophet’s (peace be upon him) saying: "Let him pray two rak'ahs other than the obligatory prayers, and then let him say." In summary, supplicating after the Taslim in Istikhara is better, though it is permissible to do so before it, and there is no reported recommendation for combining both timings.