Does Opera have config page like Firefox browser?

In Firefox browser you can type about:config in the address bar for a text-based list of features and options. Here you can modify values and add new entries.

Does Opera browser offer a similar feature?

Reason behind question:

Firefox allows you to add a feature like this:

I'm looking for a way to do this in Opera browser.

2 Answers

I found opera-mac-internal-pages-and-more that contains lots of information that you could try.

I quote some of them here:

opera://about/ About Opera, Update check, Install information opera://settings/ Manage browser settings opera://themes/ View and manage Opera themes and wallpapers opera://settings/passwords/ View and manage passwords opera://bookmarks/ View and manage bookmarks opera://extensions/ View and manage installed extensions opera://history/ View and manage browser history opera://downloads/ View and manage downloaded files 

I don't know if there what exactly you search, but there many settings:
opera://flags
source - (newer than this post, but maybe any strangers find it earlier)