First let me thank you and congratulate for creating outstanding piece of programming.
One thing I think it would be useful is adding support for hotspots in annotations.
Currently even if style used in annotation is marked as hotspot with SCI_STYLESETHOTSPOT it is simply ignored. It would be nice if hotspots were possible in annotations or at least
add a notification for annotation clicked and changing cursor to normal when mouse hovers over annotation.
Why I think it is useful?
Let me give you an example:
Suppose that we use annotation to display error / warning messages in the editor. Now clickable annotations allow displaying extra help/explanation when error message is clicked.
Currently a workaround is to handle normal lclick/double click notifications and check if line has annotations attached but this has 2 disadvantates:
a) one can not differentiate between annotation lines (if there is more than one per line of text)
b) mouse cursor shape (text entry) is misleading because it suggests that annotations can be edited while they are read-only so text-entry mouse cursor does not make too much sense to me.