Middle-click on non-link images opens new blank tab

[gue5t gue5t]

To reproduce:
Load a page which is just an image, or which contains an image that is not a link. (e.g. <http://the-witness.net/news/wp-content/uploads/2013/11/Witness_Ruins.jpg>)
Middle-click the image. A new tab opens.

I also see new tabs open in the same fashion if I quintuple(!)-click an image in this situation, or if I double-click the scrollbar grip.

This is with most recent bzr trunk, GTK2.

[paibieng (akjdoiqjwodiasd)]

Related? Middle click on scrollbar doesn't go to position as expected, but opens new tab instead

Midori 0.5.8 ((null)) Midori
GTK+ 3.8.8 (3.8.8) Glib 2.36.3 (2.36.3)
WebKitGTK+ 1.8.3 (1.8.3) libSoup 2.40.3
cairo 1.10.2 (1.10.2) libnotify 0.7.5
gcr No granite 0.2.3.1
Platform X11; FreeBSD amd64

[gue5t gue5t (gue5t)]

Yes, this is all the same bug.

[gue5t gue5t (gue5t)]

Other issues with the same underlying cause include right-clicking on the scrollbar trough opening the tab menu and right-clicking individual tabs resulting in a menu with [separator, new tab, undo close tab] at the top.

[quassy (quassy)]

Cannot confirm this with a singly middle-click in 0.5.10 (GTK3), but a double middle-click on basically any non-link area (including scrollbars) will also open a new tab.