@OP id do a full uninstall. I had the same problem but Synapse only detected it on initial launch and I wasn't able to do anything. I Force closed, and it was gone for ever but showed it when I right clicked on the icon in the taskbar. I ended up doing a full uninstall through finder / applications / Razer uninstall or something like that. Then I found a GitHub that gave me the option to finally change the colors and thats all I cared about.
I can't post the link here but go to reddit and search "Razer Synapse Big Sur m1" I just posted a thread and hopes it helps!
Djleed
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