missing TIFF image preview in document editor

[OliverSieberling]

Describe the Bug

The image preview in document editor is missing (at least) for .jpeg and .tiff files.

Steps to Reproduce

1. Go to document editor
2. Add .tiff ~or .jpeg~ image
3. See error (missing preview)

Expected Behavior

image preview for each document image

Actual Behavior

no image preview for certain file types

Additional Information

tested .jpeg image (github doesn't support .tiff images)

[ulliholtgrave]

Related to #196

[timobrembeck]

I cannot reproduce the problem for JPEG files. Since JPEG is essentially the same as JPG, I don't see a reason why it wouldn't work. The example image works for me, but probably GitHub re-encodes this during upload, so I doubt it is exactly the same file you encountered the error with. So if you can still reproduce the error, please let us get the picture another way.