When I enter it into the Display Filter box the box goes red. I'm wondering why, and if I can diagnose it better. I'm by no means a Wireshark pro and I got this little gem for ChatGPT I admit ;-) FYI this is what ChatGPT wrote:
To filter for NOTIFY packets that lack a UUID in Wireshark, you can use the filter "!(ssdp.nt matches "uuid:.*")" and "ssdp.type == NOTIFY" together.
This filter uses the "!" negation operator to match all NOTIFY packets that do not have a UUID in the NT field of the SSDP packet. The "matches" operator is used in this case because the filter is looking for the occurrence of a specific regular expression pattern.
I'm using Version 3.6.2 (Git v3.6.2 packaged as 3.6.2-2)