It does seem odd – that there's what seems like multiple, conflicting notification/bubble on/offs.
Or maybe it's just me.
You might try turning:
Settings > Notifications > Advanced settings > Floating notifications ... 'Off'. Then re-tweak it as needed.
Then go to Google Messages > your account icon > Message settings > Notifications ... to
tweak your 'Notification types' on or off.
... & ...
Message settings > Bubbles ... to turn Bubbles 'Off'.
Then you can re-tweak > Bubbles to 'Selected only' &c, as you desire. Hope that may help.
MI Super Spartan ?=)
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Whatta'ya think of the Jonathan Smith hiring? I didn't like it; I thought he should've stayed put at his Beaver alma mater.
But I guess he would've then ended-up in the West Coast conference. Which is so upside-down; I still can't hardly believe that the mega corporate networks were allowed to kill the Pac-12 ! While the NCAA just sat back and did nothing w/regards to teams jumping [conference] ships and with regards to conference revenue disparities!