Open bookmarks with one click
To open a bookmark from the sidepanel you still have to click twice. This should be able with one click. Every other browser can do so .
The developers have said they will think about this. They may also offer a drop-down menu with one-click, instead.
Right now, the requirement for double-click is intentional. The side panel is not just to find your bookmarks, but to edit them. And trying to edit bookmarks when a single click always takes you to the bookmark destination, can be a real pain.
For my part, my "drop down" that offers one-click access is a folder at the far left edge of my Bookmark Bar that contains all of my other bookmarks. I can click on it just like a drop down menu, hover thru the folders to the desired bookmark, and click it once.
At least that way, I can see everything without waiting for scrolling. In the panel, I can't see everything, and I can't drop into folders by hovering.
Actually, one can open bookmarks from the side panel with a single click.
Use middle-click to open bookmarks in the background.
In the meantime there is a setting to open bookmarks with a single click in the bookmarks section of the preferences.