Classes/Console/Command/BackendCommandController.php
public function lockForEditorsCommand()
    {
        $this->ensureConfigValueModifiable();
        $lockedForEditors = $this->configurationService->getLocal('BE/adminOnly') !== self::LOCK_TYPE_UNLOCKED;
        if (!$lockedForEditors) {
            $this->configurationService->setLocal('BE/adminOnly', self::LOCK_TYPE_ADMIN);
            $this->outputLine('<info>Locked backend for editor access.</info>');
        } else {
            $this->outputLine('<warning>The backend was already locked for editors, hence nothing was done.</warning>');
        }
    }
public function lockForEditorsCommand()
    {
        $this->ensureConfigValueModifiable();
        $lockedForEditors = $this->configurationService->getLocal('BE/adminOnly') !== self::LOCK_TYPE_UNLOCKED;
        if (!$lockedForEditors) {
            $this->configurationService->setLocal('BE/adminOnly', self::LOCK_TYPE_ADMIN);
            $this->outputLine('<info>Locked backend for editor access.</info>');
        } else {
            $this->outputLine('<warning>The backend was already locked for editors, hence nothing was done.</warning>');
        }
    }
Lock backend for editors

Deny backend access, but only for editors.
Admins will still be able to log in and work with the backend.

@see typo3_console:backend:unlockforeditors