Looks like so. If you open your project with VSCode and search "tmp" you'll find some "tmp" folder references. Add a watch exclusion on your PM2 or something (if possible)
Though Wappler does handle it weirdly, the folder is named "/tmp" (in the source-code) instead of "tmp" or "tmp/" - for those that know Linux/Unix this will mess with their heads
Errors like these will haunt you forever, I still get anxiety from those
I can only gently guide you in your detective work: Is this an error thrown by PM2 or is it Wappler NodeJS printing to the console (and therefore shown in PM2 logs)?
It would help if you put the steps used in that SC, because a simple SC with just Set Value step probably wouldn't cause that. It's one of the steps that's causing a temporary file to be written, maybe some CSV or image manipulation stuff