You can get filename collision copying from Ext2, Ext3, Ext4, NTFS, ZFS, etc to FAT32, though it might be a problem in the copying utility. It's to do with Case Sensitivity.
Also multiple . can cause problems with the stupid default in Win Explorer of hide file endings.
a . at start and a ~ in certain positions can be a problem
Longer filenames can be fine insitu but cause failure later if total path length for a filesystem or OS is exceeded.
Even now on Windows some less likely three letter or four names ending in : are actually still a problem. Potentially CON, LPT, PUN, not just obvious COM1: to COM4: (or up to 255 on Proper versions of Windows)
CDFS and Joliet are not quite the same (burning to CD) and differ from Mac, NTFS and EXT4.
Some applications don't cope with accented letters.
Some don't like - and others don't like _
& can be a problem
/ or \ may be path separators. Amazingly for a while before DOS4, I think, you could make - be the option char and then DOS used same path separator as UNIX.
There is a filesystem that allows ANY character, which makes for great importing and scary exports...
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