Bookmarks opened when bold text using keyboard shortcut
I meet issue when using Google Docs, and try to bold some text. Vivaldi opens bookmarks page and move focus to it. Text is bold too, so function is working. I have tested it on Google Docs, Zoho Docs and Office365.
I think there should be an exception list for well known sites like Google Docs, Zoho Docs and Office365 etc. to block default Vivaldi's keyboard shortcuts there.
That is a known bug whose fixing is waiting for progress.
Open Vivaldi Settings → Keyboard
Go to section Window
Go to Bookmarks field
Mark and delete the Ctrl+B with Del
Add your own shortcut.