How to undo 'hide blocks' ?

(This is a template, feel free to delete it.)

i 'accedently' marked a bunch of blocks with 'hide'. whooups!

i tried r-clicking the category background, but didn't find anything useful
image

example: (dev version of buttonclicker)
https://snap.berkeley.edu/embed?projectname=Button%20Clicker%20dev&username=jayrsnap&showTitle=true&showAuthor=true&editButton=true

If you click "hide blocks" it should give you a list of all the blocks in your project, primitive and custom, with checkboxes. You can check and uncheck boxes to control which are hidden. If you right-click on the list, it gives options select-all and select-none.

I think the option should be changed to hide/unhide blocks

Too wide for Jens, I'm guessing. Maybe (un)hide blocks.