Undo last vertex added in Geoprocessing widget tool?

[JohnGrogan1]

I have a Geoprocessing service (written in Python) used in a WebAppBuilder application (Geoprocessing widget). For a GPFeatureRecordSetLayer parameter the drawing tools work well, but when the Escape key is pressed I would like to undo the last vertex digitised rather than delete the complete shape.  I am fairly proficient in Python, but less so in JavaScript/widget customisation.  Any advice welcome.

[JohnGrogan1]

Anyone able to provide any advice on this?

[RebeccaStrauch__GISP]

I have noidea if this would work.... but have you tried CTRL-Z  yet?  That is how you would undo a single vertex add (one at a time) in a regular ArcMap edit session.  I'm not sure if that would work in a GP service or not.

[JohnGrogan1]

Thanks for the suggestion but CTRL-Z doesn't work.