Toggle Thumbnail - Lumetri•Creative•Look's thumbnail

The thumbnail of source in Lumetri tab, below Creative's Look,

occupies much verticle space.

If a toggle to collape is added to the thumbnail image, then Curves 

(which is just below Creative & has 2 toggles options) or other lower section

have a greater chance of fitting in choice Workspaces.

For me, almost always, I don't need to see that thumbnail. 

- gramps