I've updated the old mozturbo using the code from SM-1.19 for Firefox, SeaMonkey and Thunderbird, 3 binaries, one package.
https://bitbucket.org/dryeo/mozturbo/downloads/These will preload the DLLs used by the various packages. The main reason for this is that our kernel has a bug, see
https://mantis.arcanoae.com/view.php?id=2194. Basically when using high memory and closing an app, the memory that the DLLs allocated is not unallocated, leaving zombie holes in memory and eventually running out of high memory. Even without using high memory, this may help memory fragmentation.
Install with the browser or email client closed. Simplest is to put it in the working directory where the DLLs are located though it has an option to pass the location to it, create a program object, put in your startup folder with the -l (L) parameter and start it or better, reboot. Use programs as usual. You can use Theseus to keep track.
I've had good results using it with SM and TB, haven't tested too much with FF. Others have reported some problems with FF, low memory usage or not fixing slowness on restart.
Anyways shouldn't hurt, it has a command to unload the DLLs if needed. Run without parameters to see options.
Should work with most versions of Mozilla, targeted at 45ESR and 38ESR