Issue #3278415 by nod_, lauriii, catch, Wim Leers, longwave, xjm, claudiu.cristea: Remove usages of the JavaScript ES6 build step, the build step itself, and associated dev dependencies

Issue #3253148 by mherchel, longwave, ckrina, droplet: Remove IE from core's browserlist, remove non-essential CSS importing and recompile assets

Issue #3101543 by lauriii, bnjmnm, ravi.shankar, alexpott: Update core JavaScript dependencies listed in package.json

Revert "Issue #3101543 by lauriii, bnjmnm, ravi.shankar: Update core JavaScript dependencies listed in package.json"

This reverts commit 2dadb738.

Issue #3101543 by lauriii, bnjmnm, ravi.shankar: Update core JavaScript dependencies listed in package.json

Issue #2592925 by Fabianx, Sagar Ramgade: Harden drupalSettings selector against XSS when CSP is enabled

Issue #2548195 by nod_, JohnAlbin, madhavvyas, sriharsha.uppuluri: Only use single quotes in JavaScript and update .eslintrc

Revert "Revert "Issue #2510104 by pwolanin, nod_, Fabianx, Wim Leers, droplet, Pere Orga: Convert drupalSettings from JavaScript to JSON, to allow for CSP in the future""

This reverts commit e8e883f9.

Revert "Issue #2510104 by pwolanin, nod_, Fabianx, Wim Leers, droplet, Pere Orga: Convert drupalSettings from JavaScript to JSON, to allow for CSP in the future"

This reverts commit 94615a13.

Issue #2510104 by pwolanin, nod_, Fabianx, Wim Leers, droplet, Pere Orga: Convert drupalSettings from JavaScript to JSON, to allow for CSP in the future