In 2019, the Green Bay Packers hosted the Houston Texans for a series of joint practices during training camp. The two teams, which would play a preseason game at Lambeau Field a few days later, met at Ray Nitschke Field for two days' worth of joint practices.
In 2021, the Packers will again practice with another NFL team, with this year's "opponents" being the New York Jets. Like the Texans in 2019, the Jets will play a preseason exhibition at Lambeau Field, a game scheduled for August 21st. The two teams will practice together twice, on August 18th and 19th.
Green Bay of course did not practice with another team in 2020 due to the COVID-19 pandemic.
The 2019 practices were notable mainly for an injury that took place. Then-rookie tight end Jace Sternberher suffered a concussion from a big hit by Texans cornerback Lonnie Johnson, which led to some significant scuffles between the two teams. Sternberher would return a few weeks later for the Packers' preseason finale, but suffered a knee injury that sidelined him for much of his rookie season.
Aside from Family Night on August 7th, the Packers have not yet announced their complete training camp practice schedule, nor have they formally revealed plans for having fans in attendance. Stay tuned for any updates on the full practice schedule.