There are some event parameters that are useful to send with every event. Google has a helpful guide here which even covers the case where you have multiple tags (I'm running GA4 and UA during the migration and this isn't unusual). You're supposed to call gtag set before calling config on each tag. This isn't working for me though, I see nothing coming through in the debug view.
Calling set before config works fine for user properties (my journey of discovery yesterday) but unless I was doing something stupid that I haven't seen yet no dice for event parameters. The code above uses the config method of initialization with a shared object to prevent duplicating code. This seems to work fine.
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