The new start page optimizes your browser’s memory usage, as it is now one instance, no matter how many start-page's tabs you open. This feature is still under development, and if you notice it causing any problems, it can be disabled in opera:flags#shared-start-page.

Please take a look at the comparison between how the start page loaded before, and how it loads now with the new mechanism.

Before

After

 
Opera system requirements update: please note, that we’ve dropped support for OS X Yosemite. "
 
   

 
The Chromium has been updated to version 78.0.3904.17.
 
   

Yes, DoH is experimental feature, and it's disabled by default. Most probably the flag will stay in place, even if it will be enabled by default in the future, so you should be able to disable it as you wish.

Known issue: [Mac] Tab switching shortcuts do not work."
 
Some of fixes and improvements:
- DNA-80423 [Mac] 3-finger swipe (back/forward) does not work.
- DNA-80583 [Mac] Certificate dialog hidden after switching to another tab.
- DNA-79610 Crash after detaching tab with javascript dialog.
- DNA-80304 Crash at ui::EventHandler::~EventHandler.
- DNA-80965 Renderer crash when going to opera://inspect.
- DNA-81025 Crash at content::WebContentsImpl::AddObserver(content::WebContentsObserver*).
 
The Chromium has been updated to version 78.0.3895.5.
 
   

Hi, thank's for your effort in trying to solve my "problem" with side bar. ( I replied to your last message the following day, but it's not there ????.)

Concerning DoH, as far as i am concerned it is disabled.

I have dnssec on my firewall, and do not trust the cloud.

Btw, i just red that opendsd will disable that feature.
link to article here

This past spring we released Opera Reborn 3, introducing a redesigned interface with features like light and dark themes, so that your browser can be adjusted to your mood, and help you focus on your browsing. Today we are continuing the R3 design with a new drop-down list for search suggestions in the address bar.

The new drop-down list is displayed over the page with an overlay mask for visual clarity. A suggested list of visited websites from your History, Bookmarks or Speed Dial, includes different icons, bolded titles and parts of links, so you can easily recognize what you are looking for.
 

 
Bookmarks in the sidebar panel

We are also working on a brand-new look and layout for bookmarks in the sidebar panel, which we believe will be more accessible when browsing. You’ll be able to quickly and easily get back to saved websites, or if you’re not a bookmarks fan those you frequently visit.

When you click on the heart icon in the sidebar, which opens the panel, you’ll see a layout, that reflects exactly what’s in the standard Bookmarks Manager view. In this sidebar panel view, you can easily edit or delete bookmarks, or folders.
 

 
DNS over HTTPS (DoH)

When someone types a website address, like www.opera.com, the browser has to translate it to a URL code on the Internet, such as 35.158.61.69. This is done through DNS, one of the oldest surviving parts of the Internet. By today’s standards DNS is too trusting, so various ideas are being tested, to see what can be done to make it more robust.

The two main ideas are DNS over HTTPS (DoH), and DNS over TLS (DoT). Both have pros and cons, so it’s still uncertain which the Internet will eventually use, but we’ve decided to give DoH a go.

In this developer release, there is a flag in opera:flags (opera://flags/#opera-doh) that enables DNS over HTTPS (DoH) through Cloudflare’s 1.1.1.1 servers. It is still experimental, but please turn it on, and let us know about your experience. Please note, that if requests can’t be handled by Cloudflare, we will still fallback to your local DNS server. This is so you can still use Opera on internal networks, or behind firewalls.

The option is available when the #opera-doh flag is enabled.

Please also note, that there is no macOS builds for this version.
 
Some of fixes and improvements:
- DNA-79137 Crash at opera::installer::OptionsScreen::OnLanguageChanged.
- DNA-80400 Top 1px line on ‘New tab’ button is inactive.
- DNA-80530 Turn-off button in Adblocker pop-up doesn’t work.
 
   

Opera-dev version is 65.0.3425.0

--disable-gpu does not change anything beside throwing a new error code like for settings

[4983:4983:0901/182158.222684:ERROR:CONSOLE(0)] "Unchecked runtime.lastError: Cannot open URL "chrome://extensions/" in an incognito window.", source: chrome://startpage/ (0)

Starting opera-dev from consol (terminal) or from panel as application with/without switches always give same result

Thank's for your time ... and patience

Nope, no snap here. I am on arch linux and i use herecura repo for opera-dev.

Have you installed the Opera developer from snap by any chance?

I have 3 links activated in opera sidebar : bookmarks, extensions, settings

Steps to reproduce problem

Open opera in private
click sidebar "link" extensions .... nothing append ( not working ) was opening in additional not private opera window prior to version 65
click on settings ... nothing append ( not working ) was opening in a not private opera window prior to version 65

n.b. error output from consol if settings is click : [5080:5080:0831/185252.895977:ERROR:CONSOLE(0)] "Unchecked runtime.lastError: Cannot open URL "chrome://settings/" in an incognito window.", source: chrome://startpage/ (0)
No output/error for extensions in consol

Regarding sidebar and the Settings what you mean by "not working", at all or something else?