In case anyone finds this of interest, we have to keep a very close eye on memory usage by FileMaker on our Citrix and RemoteApp servers. The memory leak in the last version cost us quite a bit of money as we had to keep increasing the RAM allocated to each server as each user's session consumed the available memory, particularly those who didn't log out at night.
However, the biggest RAM gobbling culprits are ourselves. With each of us developing on our cloud servers using FileMaker Pro Advanced, in particular when using the script debugger and data viewer, the amount of memory used can easily average 4 to 6 times that of a normal user, over 1.5 to 2Gbs is quite normal, hence we try to spread ourselves across different servers.
Screen shot below taken from a combination of Pro v15 and Pro Advanced v16 (2nd in list).