M
@guigirl
First of all thank you very much for the quick and valid reply! Well, i would like to give a few hints in what i have learned in solving my problem and what might be useful for others.
The culprit of the Private Window instant crashes was my very old Preferences file (411 kb big).
Copy/Paste whole profiles including the registry key does not work.
Import Bookmarks, History and Settings and Passwords in a clean new profile does not work as expected.
If the old profile got corrupted over years, there is now no way to 'repair it', just leave it alone. What i have done is:
Copy corrupt Profile-folder 'Default' to desktop; export registry key CURRENT_USER\SOFTWARE\Vivaldi\PreferenceMACs\Default to desktop and replace in the reg file the Default with Profile 1:
[HKEY_CURRENT_USER\SOFTWARE\Vivaldi\PreferenceMACs\Profile 1]
[HKEY_CURRENT_USER\SOFTWARE\Vivaldi\PreferenceMACs\Profile 1\extensions.settings]
Export Passwords in csv (Flags enable 'Password import'), very important
Delete my Standalone installation whole Vivaldi Folder and whole Vivaldi registry key; install new standalone snapshot and ticking make default; create new profile (it's always 'Profile 1' on a clean install); exit Vivaldi.
Delete the 'Profile 1' reg key in Vivaldi and import my edited key in registry; rename the Default profile folder from Desktop to 'Profile 1' and copy to 'User Data'
Launch Vivaldi; click on Default profile button and launch the the other profile: everything from the old corrupt Default profile is there, except Login Data of cause; exit Vivaldi.
Copy Bookmarks and History from 'Profile 1' to the fresh new 'Default' profile. With the two Profiles side-by-side i redo in the new profile what i liked in settings, extensions, theme and so on in the faulty profile (not installation-wide flags, they don't survive this procedure, take a note before).
Here is the thing
After applying almost all settings, extensions, theme and stuff from the corrupt profile in my new profile, the CPU usage is just a fraction of what it used to be on the faulty profile. This is true even with both profiles running. With 50+ tabs open combined in both profiles the CPU usage is around 0,4 percent when not typing. It was idle never below 7 percent before. Also, the AMD-GPU-bug is gone, meaning, my graphiccard resets always to normal state. My Vivaldi Browser is now way snappier and cooler on CPU than before (Preference file is just 39 kb); i am happy the Private Window crash occurred, which is now of cause not the case anymore (but still in the other corrupt Profile when i try it there).
Yes, i have applied all my flags as they where before.
Disabled: #enable-quic
Enabled: #enable-gpu-rasterization, #username-first-flow, #PasswordImport, #omnibox-tab-switch-suggestions, #enable-parallel-downloading, #back-forward-cache
✌🏻 Mike
