Whether the sidebar pops up should be optional

[mingyEx]

I think the left sidebar of codewars should have a function similar to www.octotree.io's Show sidebar on hover , it should be able to choose whether to pin it, to prevent when my mouse accidentally moves to the left sidebar,
If I click the mouse, I will accidentally click on the link that pops up.

[JohanWiltink]

Yes please.

( A tooltip on mouseover the pinned bar would be nice. )