We have all seen it at some point. A common error in WordPress is a PHP memory limit error. This happens when WordPress doesn’t have enough memory to achieve what you want. It can be caused by poorly written plugins that will continue to run a procedure until the installation runs out of memory and of course WordPress memory consumption increases with the amount of modifications. Simply the more plugins you install and keep activated , the more memory power your website needs.
In WordPress 4.7, the core developer team decided to make various changes in the editor (TinyMce WYSIWYG), including removing the underline and justify buttons and rearranging some of the toolbar buttons. If you don’t want to change the way you edit your content and/or don’t want to confuse your customers with a new contribution interface, there is a simple and lightweight plugin that will set the editor style back to its previous state.