I've seen this before, but never attributed it to anything other than unintentional user error.
The way it happens to me is that the Zimbra object I thought had focus really doesn't. I therefore wind up right-clicking on what the browser thinks is just part of the plain web page and the browser gives me the browser context popup instead of the Zimbra Javascript popup I was hoping for.
It happens most often to me when I am right-clicking on an email in the subject list pane. I've learned there to click the subject, not the message appended to the subject line.
In your screenshots, notice how the folder in the shot where you get the Javascript popup has a faint black border, but in the other screenshot where you get the unwanted browser pop up the folder is merely highlighted?
That's what I see too for emails highlighted in the subject list pane.
Not sure what if anything can be done, and at least for me it's a very minor annoyance I hadn't really thought about until I saw your post.
Hope that helps,
Mark
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L. Mark Stone, CIO
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