Will setting a multicast destination address to FFFF.FFFF.FFFF make it a broadcast?

I’m working with a device that sends out UDP packets on a multicast address, however I see some packets addressed to the multicast group IP with a MAC address of FFFF.FFFF.FFFF. From what I’ve read my best guess is that this is an attempt to do a network wide broadcast from the multicast group.

Here’s what I know:

Multicast sends packets only to devices that are “subscribed” to the multicast group. Each multicast group normally has its own MAC address based on the IP address of the multicast group. A multicast packet can therefore be determined by looking at the multicast address.

A broadcast goes out to every device on the network. To send a broadcast the destination MAC address should be set to FFFF.FFFF.FFFF. I’ve also heard that broadcasts can be thought of as a special case of multicast. My question therefore is, does setting the destination MAC to FFFF.FFFF.FFFF the only change that is needed to change a multicast frame to a broadcast frame? If not, what else must be changed?

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