Send Response To Browser without DB save confirmation
The big question to ask is: what happens when it doesn’t work? (For whatever reason)

In your case, the user will probably think it worked, only to find out later that it didn’t and will most likely think “stupid app, I just changed this”. You may be okay with it. I wouldn’t. The people paying me probably wouldn’t either. 

And what a blessed career you’ve had as a developer if you believe a DB operation failing is such a very rare occurrence. Specially when deployed to production.