Does the Friday Imam offer "Tahiyyat al-Masjid" (Two-Rak'ah Prayer for Greeting the Mosque) before the sermon, and is it permissible for him to sit in the mosque for a period before ascending the minbar?

The Sunnah for the Friday preacher is not to come to the mosque until the time for the sermon begins, whereupon he should ascend the minbar directly without performing the prayer of greeting the mosque (Tahiyat al-Masjid). This is indicated by the actions of the Prophet, peace and blessings be upon him, and it has been explicitly stated by An-Nawawi, Ibn 'Uthaymeen, and Sheikh Al-Shuraim. Ibn 'Uthaymeen holds that the preacher arriving early at the mosque before the sermon time is contrary to what is correct. Al-Shuraim clarified that arriving early is not forbidden, but it is contrary to the Sunnah, and he noted that some mosques' specific circumstances might necessitate the preacher arriving early.