First off, as mentioned below, this appears to be a bug with the base game, not this AddOn. I'm creating a ticket for it anyway in case you can come up with a workaround for it.

What steps will reproduce the problem?
1. Ensure that the "Show / Hide" module is enabled and that "LFG" is disabled (always hidden)
2. Join a group through the Group Finder, preferably one with 10+ people for maximum effect
3. Right-click on your portrait to bring up the context menu. It should disappear within a few seconds (presumably, when the queue data for the group is updated)

What is the expected output? What do you see instead?
The context menu should not disappear on its own, but it does.

What version of the product are you using?
Chinchilla 2.7.3 on WoW 6.2.0

Do you have an error log of what happened?
No

Please provide any additional information below.

This appears to be a Blizzard bug: hiding the QueueStatusMinimapButton frame also hides the context menu. This only happens with this one frame; hiding any other minimap buttons (or any other frame in general) does not also hide the context menu. This is a very annoying bug; it makes it almost impossible to do anything with the context menu (like, leave group) in any moderately-sized LFG group until enough people have left that the rate of LFG status updates (and therefore menu-hidings) is slow enough that you actually have time to click an option before the menu disappears on you.

More specifically, the problem stems from ShowHide.lua, line 104 (the SecureHook call in ShowHide:HideFrame()). For easier debugging, replace it with this:

self:SecureHook(frame, "Show", function(self)
print("Hiding " .. self:GetName())
self:Hide()
end)

Then observe how when you're in an active, populated LFG group, you get constant "Hiding QueueStatusMinimapButton" which results in the context menu disappearing.

Here's a .gifv of the issue occurring: http://i.imgur.com/XWdVtTv.gifv