The **eslint-plugin-require-trailing-comma** is an ESLint rule that enforces the presence of trailing commas in JavaScript array and object literals, promoting consistent line‑by‑line editing. It’s aimed at developers who value code consistency (especially when reordering, adding, or removing items) and who are not targeting legacy browsers like IE 8. The plugin works by default on multi‑line structures, with an optional “all” mode to also require trailing commas on single‑line literals.