I use Netguard without Root.
However, the question is not: How can I best protect my privacy with a browser that obviously leaks my data to quite a few third-party services.
The question is: Should I be using Opera, if they are using so much tracking code in their app.
For me the answer is totally clear.
Uninstalled Opera, now using Firefox and Chrome as second browser.

According to Exodus-Privacy Report *1 the Opera for Android App contains tracking code for ten (10!) Trackers. Specifically these are:

• AppsFlyer
• Facebook Ads
• Facebook Analytics
• Facebook Login
• Facebook Share
• Flurry
• Google Ads
• Google Firebase Analytics
• Inmobi
• LeanPlum

In your Privacy Policy for "Opera for Android" *2 you mention:

• Google Location-Services
• AppsFlyer
• AppBoy
• AdMarvel (which uses Facebook SDK)

That leaves Flurry, Inmobi and LeanPlum totally unaccounted for in your privacy policy. Google Tracking seems to be more than just Location-Services and AdMarvel does not just add Facebook SDK, but specifically adds Facebook tracking code.
I believe you should update your privacy policy accordingly.

Personally, I was shocked to learn that Opera for Android contains so much tracking code from so many different companies, which all monitor the websites that I visit. I am now actively selecting apps based on privacy and protection of my personal data and I am afraid that I will have to look for a new web-browser. Very disappointed!
Bye Bye Opera.

*1 https://reports.exodus-privacy.eu.org/en/reports/52281/
*2 https://www.opera.com/de/privacy/operaforandroid

The Google Search box on the speed dial start page can be disabled.

You just have to tick the following box in settings:

opera://settings/ > Browser
Section 'Start Page'

Hide search box

Check whether this box is ticked or not :

opera://settings/ > Privacy & Security

Use a prediction service to help complete searches and URLs typed in the address bar

I couldn't get to 'disable hardware acceleration' because opera://settings was giving a 'page crashed' error as well.

I did check that Nividia Optimus settings were still 'use integrated graphics', no changes made.

I was going to rename my profile folders to force Opera to create a new profile on next start, but ...

After restarting my computer this morning, Opera is fine again. No Problems.

The old off/on Trick still works it's magic. Very strange.

On your speed dial page look for the 'Easy Setup' symbol in the top right corner.

Open 'Easy Setup'
Find section 'Appearance'
Disable 'Show speed dial suggestions'

Opera has totally hung itself up. It was open in the background with one tab displaying a respected newspaper site. When I switched back to Opera it displayed the message "Page crashed. Unfortunately something caused this page to quit. It might have been an extension conflict or some other reason. Please try reloading the page."
Reloading the page does not help.
Closed Opera, cleared cache and everything that can be cleaned with CCleaner, restarted Opera, but it still only diplayed "Page crashed" warning.
Tried to load about://extensions to deactivate all extensions, but that also just displays the error warning. Even about://blank gives the error warning.
What do I do next?

Here the Problem was fixed with the newest nVidia Optimus driver.
Opera is now fully functional again.

Opera not working after Windows Update to 1709.
Opera starts up and at first looks ok, but browser window just shows black, no matter whether calling a webpage or on bookmarks, settings, etc.

Uninstalled Opera and deleted User Settings.
Cleaned all Opera related entries from Registry.
Installed Opera 48.0.2685.52

Same problem as above.