# Add "Full Screen" button to main toolbar

**URL:** <https://pdfjs.community/t/add-full-screen-button-to-main-toolbar/1371>\
**Category:** Technical Support\
**Tags:** pdfjs-express\
**Created:** [February 11, 2022, 3:30am UTC](https://pdfjs.community/t/add-full-screen-button-to-main-toolbar/1371 "2022-02-11T03:30:19Z")\
**Posts on this page:** 1\
**Showing post:** 3

<div class="post-metadata">

**Author:** ![system](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/1X/ffbcd25c7d423db8d5acd5db201c272f4db306dd.png) [@system](https://pdfjs.community/u/system)\
**Post date:** [February 11, 2022, 3:30am UTC](https://pdfjs.community/t/add-full-screen-button-to-main-toolbar/1371/3 "2022-02-11T03:30:23Z")

</div>

**Hello, I’m Ron, an automated tech support bot 🤖**

While you wait for one of our customer support representatives to get back to you, please check out some of these documentation pages:

Guides:
- [MIME types](https://pdfjs.express/documentation/get-started-viewer/blazor/mime-types)
- [Customize toolbar in viewer - Examples - Add a custom save button](https://pdfjs.express/documentation/ui-customization/customizing-header.8#add-a-custom-save-button)
- [Core engine for WebViewer - Interacting with Core](https://pdfjs.express/documentation/ui-customization/core.8#interacting-with-core)

APIs:
- [Core.Tools.MarqueeZoomTool - addEventListener(type, fn [, options])](https://pdfjs.express/api/Core.Tools.MarqueeZoomTool.html#addEventListener__anchor)
- [Adding a download button](https://pdfjs.express/api/utils/tutorial-Adding%20a%20download%20button.html#__anchor)
- [Core.Tools.FreeHandCreateTool - mouseRightDown(e)](https://pdfjs.express/api/Core.Tools.FreeHandCreateTool.html#mouseRightDown__anchor)

Forums:
- [Add custom button to the Menu](https://pdfjs.community/t/add-custom-button-to-the-menu/1093/1)
- [Disable UI buttons in](https://pdfjs.community/t/disable-ui-buttons-in/1134/1)
- [PDF.js Express Viewer not working via reverse proxies](https://pdfjs.community/t/pdf-js-express-viewer-not-working-via-reverse-proxies/1255/1)

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_[View the full topic](https://pdfjs.community/t/add-full-screen-button-to-main-toolbar/1371)._