Interesting alternative, however I agree that the sidebar should have never been removed from the speed dial. Its infuriating that Opera forces users to always have a sidebar that is completely useless while web browsing, but remove it in the one place that makes sense.
I would also go as far as to advocate that turning on the sidebar after every update regardless of settings is not serviceable. I cannot count the amount of service calls I get about turning it off on the countless machines i've deployed Opera to.
Thank you @kmielczarczyk for reaching out, it is greatly appreciated.
By any chance would the Opera team consider to bring back this function - that was really useful btw - so we can have a more enjoyable customization of Opera ?