Hello,
I've been rolling out Firefox portable to enterprise users for years now and never had this issue before version 55.
I deployed to the pc's and installed locally to the C: drive as per normal.
When users attempt to launch the exe either directly or from shortcut, nothing happens the firefox.exe process is running but browser does not launch. When I tried on an x64 pc, it launches fine.
Have tested the older vers 53.0 on an x86 pc and it launches without issue either from local drive or from our install share.
Is there a known issue with vers 55 auto detection of 32 and 64 bit pc's?