@Llysh well, others have written it already, so I will only confirm.

Remove all icons, hide sidebar, wait a bit and after next Opera update, the sidebar is back.
Hiding the sidebar is simply not permanent.

@nazozt please read the rest of the discussion here first.

@nazozt is it permanent? or until next time opera decides to propagate some social media or other useless functionality?

@Llysh well, others have written it already, so I will only confirm.

Remove all icons, hide sidebar, wait a bit and after next Opera update, the sidebar is back.
Hiding the sidebar is simply not permanent.

@Llysh Facebook Messenger pops up every now&then and the sidebar is back. I don't really care about the icons, I want the whole sidebar gone for good.

And that will never happen

@burnout426 thanks, let's see what happens

@sgunhouse I have disabled all the items in sidebar multiple times. Every now and then (and recently more often than not) some items re-appear (e.g. facebook messenger and twitter).

The sidebar that pops on the left randomly (I assume after updates?) is annoying. How can I prevent it from ever appearing again?
Please!