I am having the same problem with SSMS 19. I am using SSMS version 19.0.20209. When I recently upgraded Plan Explorer to v2023.1.3.38556 the option to open a plan in Plan Explorer has disappeared from my SSMS context menu. I now must save the plan as XML and open in Plan Explorer.
SolarWinds solutions are rooted in our deep connection to our user base in the THWACK® online community. More than 195,000 members are here to solve problems, share technology and best practices, and directly contribute to our product development process.