A Junkrat exploit resurfaced in Overwatch, which allows Junkrat players to disguise an incoming RIP-Tire.
The Overwatch exploit can be especially harmful for enemies who are targeting the Junkrat. If a Junkrat player activates their Concussion Mine and ultimate at the same time, Junkrat will be sent flying along with the RIP-Tire animation, but the RIP-Tire will not be deployed he lands.
The RIP-Tire will instead spawn at the Concussion Mine, which can be far away considering he is able to launch himself impressive distances with the Concussion Mine. This can confuse enemies and help Junkrat secure a few easy kills.
A different player posted a video of the exploit in action from some time ago. The bug was removed, but resurfaced after a bug with Junkrat's RIP-Tire was fixed. Because players are aware of the bug again, and it could be used unfairly in fights.