I noticed recently that if I have a number of groups notices to go through,the >>> (next) to cycle through them is gone once I close one of them, after cycling at least one. For example, I have notice1 -> notice2 -> notice3(front most notice). If I move it to the back, with the >>>, the stack is now notice3 -> notice1 -> notice2. If I close notice2 with the OK button, I'm left with notice3 -> notice1 but notice1 does not have a next option and I must close to get to see notice3.
If this is the correct file, looking at the code in: newview/llgroupnotify.cpp, I'm wondering if the function: void LLGroupNotifyBox::close() might need to enable the mNextBtn, if there is more than one remaining in sGroupNotifyBoxCount. This is what happens in: void LLGroupNotifyBox::moveToBack().
*Edit: My obeservation might be a bit incorrect. It seems as though the 'stack' of notice elements, each start out with the >>> enabled (even though one can only see the front one). The code shows that the action of moving the front one to the back, disables the >>> (next) button. This would be why the next button is always visible if one just dismisses the stack in the order in which they arrived. My proposed solution location may be incorrect then.
Maybe when they are moved to the back they shouldn't have their next button disabled?