New product from Rack-a-Tiers. It has breakaway knockouts on the sides near the top. I saw these at the supply house today. $8 a piece.... I don't usually go for gimmicks, but I do this kind of repair often enough that I see the value. I bought 6
https://rack-a-tiers.com/product/open-splice-junction-box/

https://rack-a-tiers.com/product/open-splice-junction-box/