Toggle for cookies doesn't work. In private mode cookies are greyed out. I assume toggling cookies will apply for private mode too.
Toggle for proxy doesn't work either (manual proxy cfg / direct connection).
I assume both are work in progress since the items are greyed out in the F12 menu as well.

Also the buttons you can add to toolbars, seem to be work in progress.
Although not all buttons are functional (e.g. enableJavaScript, enableProxy) for now, I'm missing the toggle for cookies!?

@krake, yeah, some of these toggles are currently just declared, the main issue is that we need a way to make it more obvious where these values are applied (currently such settings apply to tab and are inherited by tabs opened from it).
Related ticket:
https://github.com/OtterBrowser/otter-browser/issues/511

After reading that thread, if I may put my two cents in:
Keep it simple and functional (F12 = quick prefs/Opera Presto).
IMHO toggles should work globally as they work in every browser I've came across and as they are expected to work.
The same should apply for the toggle buttons too, just like in Opera Presto.

Edit:
Nothing against text buttons. Only drawback, they might take more space than necessary. In Opera Presto I edited the .lng file to shorten the buttons ( e.g. "Enable Cookies" = "C", etc). Is it possible to shorten the text in Otter?
Even better, in K-Meleon I've replaced the text with 16x16 px (height and width can be defined in .cfg file) .png files.

@krake, uhm, I'll need to think about that, currently most of (or all) options in menus apply to just current tab (for example hint for encoding etc.).

Setting of custom text for buttons should be available at the same time when custom icons will be added, later both should be available also for context menus.