Feedback welcome. The bug has nothing to do with case-insensitive file systems (the underlying file renames are performed with rename(2) on Linux/OS X and MoveFileExW on Windows, which can handle case changes just fine). The bug is entirely in the way Thunderbird was handling names.
Created attachment 645623
Proposed patch
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Feedback welcome. The bug has nothing to do with case-insensitive file systems (the underlying file renames are performed with rename(2) on Linux/OS X and MoveFileExW on Windows, which can handle case changes just fine). The bug is entirely in the way Thunderbird was handling names.
I've only tested this on OS X.