A Vivaldi update described as ‘minor’ includes mitigations for the Spectre and Meltdown vulnerabilities. The changes are intended to make exploiting Spectre and Meltdown much more difficult in the context of Vivaldi itself. Other browser makers have released — or are working on — similar updates.
The announcement for Vivaldi 1.13.1008.44 is light on details, and there’s no link to a change log. The new version number isn’t even mentioned.