Whenever Twitter announced its intends to enter the relationship space last might, panicked investors delivered market frontrunner Match Group ’s stock tumbling toward its worst fall ever.

Whenever Twitter announced its intends to enter the relationship space last might, panicked investors delivered market frontrunner Match Group ’s stock tumbling toward its worst fall ever. A 12 months later, they’re not too concerned. The primary competitive danger to Match’s business is apparently fading away. Facebook (ticker: FB) has yet to...