[Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9pre) Gecko/2008032900 SeaMonkey/2.0a1pre] (nightly) (W2Ksp4) See bug 425956: 1. I tried to attach a BMP file with "Auto-Detect". 1r. It was added with the "image/png" type, and looks garbled. I don't know if the file was auto-converted from BMP to PNG and that failed, or if it's only the auto-detected type which was set wrongly. 2. Then I attached it as JPG with "JPEG" explicitely. 2r. (That worked fine.) I don't know if this is a regression (bug 425607) or not: feel free to change as needed.

I downloaded the file locally and checked what `file` though the type was... $ file 425956_Dialog.bmp 425956_Dialog.bmp: PNG image data, 112 x 27, 4-bit colormap, non-interlaced Either a corrupted file or the logic in the magic file is getting confused by this image. Either way, not a bugzilla bug. --> INVALID

(In reply to comment #1) > Either way, not a bugzilla bug. Er, not so fast. Bugzilla does indeed attempt to autoconvert BMP images to PNG, so if the BMP looked fine before he uploaded it, then the translation choked or something.

The BMP file is created with Windows Paint, as 112 * 27 px, 16 colors. 'auto-detect' "compresses" the content to the left half of the image, and has a few (random, compared to the bug 425956 file) colored vertical lines in the black right half. 'image/bmp' is somewhat less wrong as the right half is all black. *** Bug 425956 attachment 312496 [details] is a (correct) JPEG file, which I converted from the BMP file using Windows Imaging.

(In reply to comment #0) > I don't know if this is a regression (bug 425607) or not: FWIW, <https://bugzilla.mozilla.org/> says "version 3.0.3+".

[Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9pre) Gecko/2008051102 SeaMonkey/2.0a1pre] (nightly) (W2Ksp4) Same bug happened with bug 405286 attachment 320487 [details]. {{ Note: Bugzilla automatically converted your BMP image file to a compressed PNG format. Note: Bugzilla automatically detected the content type image/png for this attachment. If this is incorrect, correct the value by editing the attachment's details. }}

This is likely a problem with the bmp -> png conversion based on the attachments. the application/octet-stream one is the correct one.