FRAMED_BOX_CURSOR: Any interest in a new cursor type?

[Keith David Bershatsky]

During my ongoing work on developing feature requests #22873 (multiple fake 
cursors) and #17684 (crosshairs / fill-column), I came up with a new cursor 
type for all three GUI platforms (X11, NS, and NT).  It is a hollow cursor, 
with a filled inner color, and a different (or same color) for the glyph 
character as the outer frame of the cursor.  Think of it as a picture frame 
with a different color background/inner shade and the text stands out; e.g., 
yellow outer frame, blue inner filled shade, and yellow text.  I have simple 
tests to determine whether the cursor appears in the active/inactive windows 
(so colors can be different in those windows), which is needed on the NS port 
because it uses a separate function to colorize the text (which does not have 
access to the active/inactive arguments of the other cursor drawing functions). 
 I included a test for whether the region is active and whether PT is at the 
beginning or ending of the active region, and the colors are different depend
 ing upon those situations.  The colors can be customized by the user, with the 
outer frame of the cursor being the cursor-color we are all familiar with and 
the cursor-type is 'framed or "framed".  It suffers from the same disadvantage 
as the FILLED_BOX_CURSOR in so far as a the face of an overlay underneath gets 
covered up (trumped) by the cursor.  I can extract the proof-concept code from 
the features that I am working on, but thought that I should check first to see 
if the Emacs development team has any interest?