Did Omar ibn al-Khattab, may Allah be pleased with him, destroy crosses in the lands he conquered because they were symbols of polytheism, and what is the evidence for that?

Umar ibn al-Khattab, may Allah be pleased with him, made a treaty with the Christians of Syria, which came to be known as "The Umarian Covenant." It stipulated that they should not openly drink their wines nor display their crosses and pigs. Umar did not order the demolition of crosses, but rather forbade their public display. Ibn al-Qayyim mentioned that the cross is one of the overt symbols of disbelief, and that they are not permitted to raise or display it above churches, or on doors and visible places, but it is permissible to engrave it inside churches.