Only 90 days visible with this method.
In the link below you said
"edit the "Preferences" file in Vivaldi's "Default" folder with JSONedit, add the "vivaldi" object as a child of root, add the "history" object as a child of the "vivaldi" object, add the "days_to_keep_visits" integer as a child of the "history" object, set "days_to_keep_visits" to 3650"
I have the JSONedit open but am unfamiliar with "object as a child of root"
Can you reword these instructions or provide the modified text for me to copy