Bug - Deleting sketch object makes unconnected elements unconstrained

[alan.jonesXHXUF]

This is happening constantly and is very annoying! Draw a sketch, get it all defined. Delete some random element not connected to anything whatsoever and Fusion shows the fully constrained elements as unconstrained again. F3D attached. The Closed D profile is fully constrained then there is a random floating line that I drew just to measure something on the background canvas, but when I go to delete it.. well you get the idea. There's a screencast too but it's taking for ever to process, and the forum can't actually insert it without throwing an error anyway...

https://autode.sk/3ywqalD <-Theoretically a screencast url

[davebYYPCU]

Well you don't have to delete the line, to get the same result, just delete this Perpendicular constraint, and leave the line in the sketch, still breaks the status.

Best I can tell, the black / white point at this tangent point means the sketch outline is in error at all times.  Deleting the Perp constraint, allows all centre points to turn white as well.

Well known that symmetry constraint is the culprit. 

Easy fix,

Delete / trim the right hand curve, make centre point vertical, and centre line a centre line.

Might help....