Previously, by default, the fieldsets do have "horizontal margins" when sideNav shows up. However, this brings some problems to aftermarket addons like XenCarta, leading to issues that editor viewport width is not wide enough. This update locked the fieldset horizontal "margins" settings to userCP pages only (except the "signature" settings).
Notes to XenCarta users: Please set additional CSS to your extra.less:
Less:
div.block.carta-page .bbWrapper {line-height: 1.7em}
$ EOF.