新しいスナップショットが来たよ！
少なくともイベントが複数回発生する問題は解消したらしいので、興味ある人は試した方が良さそう。

Continuing work on mouse gestures ? Vivaldi Browser snapshot 1.15.1132.3 | Vivaldi Browser
https://vivaldi.com/blog/snapshots/continuing-work-on-mouse-gestures-vivaldi-browser-snapshot-1-15-1132-3/

Known issues
[Linux] Cannot use the right click context menu with mouse gestures and rocker gestures enabled with a scaled (HiDPI) display (VB-38504)
[Linux] Save password dialog does not show up (VB-38805)

Changelog
[Regression] Gestures executed multiple times (VB-38720)
[Regression] Missing number of reloading Speed Dials (VB-38679)
[Mac] Default shortcuts for next/previous tab changed to “?+?+[Arrow]” ? used to be “?+?+[Arrow]” (VB-18300)
[Address bar] Update Refresh and Home icons (VB-38767)
[Bookmarks] Bookmark indicator does not always update (VB-37274)
[Bookmarks] Can not create new bookmark from context menu (VB-38781)
[Bookmarks] Folder menu cover the bookmarks bar item when bar on the bottom (VB-10288)
[Quick Commands] Rounded corners on Quick Commands (VB-38719)
[Search engine] Prevent removal of default search engine (VB-38379)
Crash dialog isn’t localized (VB-4572)
Ghost processes after Speed Dials reload (VB-38677)
Mark active page in cycler (VB-11010)
Save password dialog is misplaced in fullscreen and maximized mode (VB-38723)
Speed Dial Update causes timeout (VB-38725)