In PhpStorm or WebStorm, the Emmet ! abbreviation for generating an HTML5 boilerplate works only in files recognized as HTML, so it won’t automatically expand in a .php file because the editor treats it as PHP code. To insert the boilerplate inside a PHP file, place the cursor outside any <?php ?> tags and use the Emmet “Expand Abbreviation” command manually from View → Context Actions → Emmet → Expand Abbreviation (or press Ctrl+Alt+J / Cmd+Alt+J) and type !. If that doesn’t work, you can enable Emmet for PHP under Settings → Editor → Emmet → Enable Emmet for: HTML, PHP, etc. Alternatively, create a custom Live Template: go to Settings → Editor → Live Templates, add a new template under the PHP context, set an abbreviation such as html5, and paste the standard HTML5 boilerplate code inside. Then, whenever you type html5 and press Tab in a PHP file, PhpStorm will insert the complete HTML5 structure without affecting PHP execution.