First - I love sidewise. It's awesome. I've used onetab for a long time and I believe I've found it's replacement. I love closing a window set of 10+ tabs and being able to pull them back up later, blistering fast, and while they are asleep there is no memory drain.
Bug: When I double click a row to open those tabs (which is the option I have set in settings), a prompt pops up asking me "Wake up X hibernating tabs?" - but the buttons of the prompt are beyond the width of the sidewise bar, and they aren't displayed.
Customer support service by UserEcho