When the Nintendo Switch launched in February, there were multiple articles and reviews claiming that the Switch's left Joy-Con was prone to frequent connection issues during normal use. (See Nintendo Switch left Joy-Con disconnects frequently. Fix?)
I've seen some claim the disconnect issue was fixed by a day-one patch, while others claim it was a hardware issue only present in early Switch models.
Were the connection issues for the Switch's left Joy-Con ever fixed? If they were, how can I tell if my Joy-Con could be affected?