Default "History Back" and "History Forward" shortcuts are unfortunate
"History Back" has 'Backspace' and 'Ctrl+Left'.
As a result it often triggers when hitting backspace while editing text fields in blogs, wikis and forums.
Same with "Ctrl + Left" which is used to jump one word when navigating text fields too.
"History Forward" has 'Ctrl + Right' which is also used to navigate text fields one word at a time and often triggers the shortcut for whatever reason.
I'm not sure who comes up with such shortcuts but they are clumsy and unfortunate.
Arguably those shortcuts should not trigger when editing text fields and that's just a bug but beyond that the very nature of those shortcuts are just error prone.
Pleas, please, please, remove those clumsy default shortcuts.
You have to remove the keyboard shortcuts by yourself. Even if Vivaldi will change their default, the updates won't change existing keyboard mappings to anyone.