Redmine

The right click menu is always rendered below and to the right of the mouse cursor. Thus it is possible to cause this menu to be rendered "off the screen". For example, if you go into issues and right click on an issue towards the bottom of the browser window, the entire menu will be rendered below the visible browser area.

If the cursor is towards the bottom of the browser window then the menu should be rendered above (instead of below).
If the cursor is towards the right of the browser window then the menu should be rendered to the left (instead of to the right).
In the degenerate case when the cursor is close to all sides of the browser window (i.e. the browser window is resized to be very small) then the menu should be rendered in the default manner.

Obviously this is low priority.

As I am not familiar with the source layout, if someone wants to point me to which source file generate the menu I would be willing to take a crack at doing this. This would be a good example to learn the code and help contribute.