Run results for: reduce concat vs flat vs concat spread

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:71.0) Gecko/20100101 Firefox/71.0

Browser: Firefox 71

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Script Preparation code:

var data = Array.from({length: 1000}, () => Array.from(Array(100).keys()));

Tests: