My six-year-old workhorse S1500M that has never had any problems will be a glorified paperweight if I install Mojave. Aaargh!
Note on Fujitsu website:
ScanSnap S1500/S1500M Compatibility Status With macOS Mojave v10.14
ScanSnap S1500/S1500M does not support macOS Mojave. There are no plans for adding support in the future since the support for ScanSnap S1500/S1500M has already ended.