This doesn't seem possible to do on the current version (1.0.303.52) of Vivaldi. Am I missing a setting for this?
Nope. That function is not ready yet.
Volunteer Vivaldi Moderator and tester using Windows 10 X64, AMD A10 8750, 12 compute cores (4C, 8G) 3.6 GHz; ASUS EAH5450 graphics; .5TB Mushkin MLC SSD; 16 GB DDR3 PC3 12800 RAM
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