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IT'S STILL IN OPEN BETA
As Google Analytics V4 is still in open beta, you need to be careful about how much you rely on it.
CROSS DOMAIN TRACKING
One of the biggest forces with Analytics V4 is there ability to cross domain track without the use of cookies.
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VIEWS REPLACED BY SOURCES
In Google Analytics V4 we don't see the views we saw in Google Analytics V3, instead you work with source.
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