Syncthing Trayzor has not been updated for a while. Syncthing Tray is the one to use now.
How to install:
Open CMD and enter these commands
winget install -e --id Martchus.syncthingtray
winget install -e --id Syncthing.Syncthing
The install is in %localappdata%.
Syncthing.exe will not be in the Start Menu.
Copy it and paste as a shortcut into
Winkey + r
%USERPROFILE%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs
Start Syncthing. Tray's icon will be in the Taskbar's group on the right.
Start it and set up Syncthing.