Manjaro 19.12 Plasma on the eMMC gives me 10548 using the Vivaldi snapshot 2.11.1800.5 (Official Build) (64-bit). I wonder what I'd get on a fresh boot with only one browser tab open.
EDIT: After further testing the only significant difference I saw was that Firefox got scores about half of the two Chromium-based browsers I tested.
Test method: Starting from power off, boot the PBP, log into KDE Plasma, open the browser and load the test page. Wait for the Plasma CPU Load Meter on my desktop to stabilize with all CPUs at less than 10%, begin the test and don't touch the mouse or keyboard while it runs.
Octane Score: 10831 2020/01/25 18:01:31 -- fresh (re)boot Vivaldi snapshot, one tab
Octane Score: 10890 2020/01/25 18:09:58 -- fresh boot Vivaldi snapshot, one tab
Octane Score: 5449 2020/01/25 18:14:05 -- Firefox Browser 72.0.2 (64-bit), one tab
Octane Score: 4999 2020/01/25 18:36:33 -- Firefox after cold boot
Octane Score: 10001 2020/01/25 18:18:25 -- Chromium Version 79.0.3945.130 (Official Build) Arch Linux ARM (64-bit), one tab
Octane Score: 9958 2020/01/25 18:26:33 -- Chromium after cold boot
EDIT: After further testing the only significant difference I saw was that Firefox got scores about half of the two Chromium-based browsers I tested.
Test method: Starting from power off, boot the PBP, log into KDE Plasma, open the browser and load the test page. Wait for the Plasma CPU Load Meter on my desktop to stabilize with all CPUs at less than 10%, begin the test and don't touch the mouse or keyboard while it runs.
Octane Score: 10831 2020/01/25 18:01:31 -- fresh (re)boot Vivaldi snapshot, one tab
Octane Score: 10890 2020/01/25 18:09:58 -- fresh boot Vivaldi snapshot, one tab
Octane Score: 5449 2020/01/25 18:14:05 -- Firefox Browser 72.0.2 (64-bit), one tab
Octane Score: 4999 2020/01/25 18:36:33 -- Firefox after cold boot
Octane Score: 10001 2020/01/25 18:18:25 -- Chromium Version 79.0.3945.130 (Official Build) Arch Linux ARM (64-bit), one tab
Octane Score: 9958 2020/01/25 18:26:33 -- Chromium after cold boot