I vaguely remember newer versions of JS/ECMAScript allow users to put spaces within numbers for readability. E.g. something like:
const age = 1 000 000;
However my linter complains, probably because it needs to allow the rule - what's the name of this ECMAScript feature?
Sadly searches for 'numeric separators JavaScript' have only found answers about formatting numbers for display to users.
You can use underscores as separators to make large numbers more readable. This is a part of ES2021 (https://tc39.es/ecma262/#prod-NumericLiteralSeparator).