在主题中居中一行

[Steven]

If you don’t want or can’t install a plugin, I also created a theme component with a few buttons

MD Composer extras

This theme component adds few formatting options in the composer : underline, align center, align right, justify and strikethrough. You can customize the text of each button in the settings, making it compatible with every languages. Exist in rtl version (change align right to align left).