cybre.space just updated to v2.0.0rc1, and I use the default Mastodon theme.

You can see how the scrollbar on the emoji box is out of view - it's past the bottom of the page, and there is no way to scroll the first ("new toot") column to show the whole emoji panel like there was in the last version.
I use the latest version of Chrome on a Mac running 10.12.6.
master (If you're a user, don't worry about this).It's the same problem with others pop-up, likes confidentillity menu :

Here on Firefox 56.
Question, how did it work before?
Before, you could scroll with the mouse to bring up the rest of the pop-up.
Yes, the column on the left would become a little bit longer than the end of the pop-up, so you could scroll down. Then when the pop-up disappeared the column would spring back to shorter again.
I think it might be connected to the way menus drop off the bottom of the screen too, and when I scroll the menu stays where it is while the toot moves upwards:

Some menu stuff still a bit not working, see #5466!
This is technically fixed because you can now scroll it into view, although indeed #5466 is valid.
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I think it might be connected to the way menus drop off the bottom of the screen too, and when I scroll the menu stays where it is while the toot moves upwards: