OS: Windows 7 Ultimate x64 (RUS lang).
Opera: 62.0.3331.72 and a few previous versions.
Favorites icon/button doesn't works in sidebar, if express-panel tab is opened. The same behavior for another buttons (icons), except Extensions and Settings icons.

Steps to reproduce: open express-panel tab. Try to open Favorites/News/History etc. from sidebar.

Steps to recover: open Setting or Extensions from sidebar. Now other icons works correctly.