Backgorund of menu is transparent when it's shown - and slight overshoot for large menus - and fixes about ootliner HOT 1 OPEN

The source is here:

https://robertinventor.online/Open-letter-to-NASA/index.js

As you'll see I also added a hook function which I use to move the main content to the right if there isn't room for the drop menu in the left margin.

Just a suggestion, you could add an empty hook function that people could populate with any action they want to do when the menu is shown or hidden.

And again, whether or not, this comment could also be a tip for anyone who wants to do what I did who wondered how to do it.

from ootliner.