Ever wondered why since a couple of weeks you cannot preview TIFF attachments (like FAX images) in GMail any more?
It’s because GMail has (hopefully soon had!) a bug handling little-endian TIFF images: the preview of your attachment might reveal someone else’s!
While fixing it, GMail seems to have disabled the preview for all TIFF images.
Jaffar Rumith found about the bug more than a year ago, then rereported it, and blogged about it (GMail + TIFF = ? « Scientia potentia est).
Soon after his blog post got published, the bug got acknowledged (hopefully that is not cause and effect).
Viewing TIFF attachments didn’t work for a while either, but now works again.
Hopefully they will fix the preview TIFF issue soon…