Have you actually opened the file in Opera? Admittedly Opera for Windows doesn't say anything about Open on the menu, but Ctrl-O does bring up a standard file dialog, and I have no problems opening a random JPEG (*.jpg) file from there. Once open, the context menu allows me to "Use image as wallpaper".
Another update. Managed to hit the icon, seems the crash is still there.
And as talking about dealing with LastPass changes it has once again changed rather reverting to an old state. During the process of crashes the browser will disable the extension so re-enabling it cause it to revert something. Not sure whats up with this.
(Sorry for the double post wasn't sure how to add this to the other one)
@drparanoid See this topic.
Basically Opera is the only browser that really review the extensions, doing it manually and they seem to have a very small team to deal with all the extensions, what causes the delays.