Desktop website not working in Firefox

In Firefox for Windows there's 2 issues that make it difficult to work:

1. The sort button for comments doesn't work. In other browsers it shows Oldest, Newest, and something else, but in Firefox the menu can't be opened. Instead it indicates that it sorts top-down or bottom-up while it doesn't.

2. When reading comments, in other browsers you only have to move the page a tad up to get the Notifications icon in focus, while in Firefox you have to scroll all the way to the top of the page to get to Notifications.

Tnx...

drftr