Mastering Chrome DevTools: Unleashing the Power of Web Debugging and Performance Optimization

Chrome DevTools is an indispensable suite of web development and debugging tools that empowers developers to inspect, debug, and optimize web applications with ease. In the workshop, we will take an extensive deep dive into the various features and functionalities of Chrome DevTools, enabling you to become a proficient user and harness its full potential.

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1. Web Development Mastering Chrome DevTools: Web Debugging and Performance Optimization.
2. Usman Ogunsola - Snr Software Engineer, Zuvvii Gaming Limited - Snr Software Engineer, Primed Heritage Limited - Co-Founder & COO, Macrosuta Technologies Limited
3. DevTools! Heard of it? Introduction Section 1
4. • Integrated set of web development and debugging tools in Google Chrome. • Access through right-click on a webpage and selecting "Inspect" or using keyboard shortcut (Ctrl+Shift+I or Cmd+Option+I). • Main panels: Elements, Console, Sources, Network, Performance, Memory, Application, Security, and Lighthouse. • Device Mode for responsive design testing and emulation of various devices. Overview Section 1
5. • Efficient Debugging • Optimized performance • Responsive Design Testing Why DevTools? Section 1
6. DOM, logging, script execution… Inspecting & Debugging Section 2
7. • The Elements panel allows you to inspect and manipulate the Document Object Model (DOM) of a web page. • Easily navigate through the HTML structure and CSS styles of elements by hovering over and selecting elements in the panel. • Edit HTML and CSS in real-time to visualize and test changes without modifying the source code. • Use the "Styles" tab to explore and tweak computed styles, CSS rules, and element box models. Elements Panel Section 2
8. • The Console panel is a versatile tool for logging messages, running JavaScript commands, and debugging code interactively. • The Console displays output from console.log(), console.warn(), console.error(), and other console methods, making it a valuable tool for logging and debugging information during development. • You can directly type and execute JavaScript commands in the Console, allowing you to test code snippets and interact with the page in real-time. Console Panel Section 2
9. Chrome DevTools offers powerful inspecting and debugging capabilities, aiding developers in streamlining the web development process. The Elements and Console panels can be seen to help enhance workflow in this regard. Take advantage of the "Sources" panel for more advanced debugging tasks, including setting breakpoints in the source code, examining call stacks, and using the "Watch" and "Scope" sections to inspect variables during runtime. Debugging Tip Learnings Section 2
10. Requests, timing, payloads… Network Analysis & Performance Optimization Section 3
11. • The Network panel records all network requests, allows filtering by request type, and provides details like headers and response payloads for effective monitoring and analysis. • Use the Network panel's "Timing" tab to identify performance bottlenecks and analyze request timelines. • Simulate different network conditions, like 3G or 4G, to test application performance and responsiveness under various network constraints. Network Panel Section 3
12. By mastering the Network panel and performance optimization techniques, you can significantly improve your web application's loading speed and overall user experience. When enabled, the “Preserve log” feature ensures that the Network panel retains captured network activity even after a page reload or navigation. It's particularly helpful when dealing with page redirects or asynchronous loading, as it allows you to analyze all network requests across multiple page interactions and prevents the loss of valuable data during the debugging process. Debugging Tip Learnings Section 3
13. Responsiveness et al… Mobile Development & Device Emulation Section 4
14. • Device Mode in Chrome DevTools allows developers to simulate how a web application appears and behaves on different mobile devices. • Access Device Mode by clicking the "Toggle Device Toolbar" icon or using the keyboard shortcut (Ctrl+Shift+M on Windows/Linux or Cmd+Shift+M on macOS). • Test responsive designs by choosing from a wide range of pre-configured devices or by customizing screen dimensions and user agents. Device Mode Section 4
15. By utilizing Chrome DevTools' mobile development and device emulation features, you can create responsive and user-friendly web applications that cater to a diverse range of devices. - Use media queries to apply CSS styles based on screen size, ensuring a consistent user experience across different devices. - Test touch interactions thoroughly in Device Mode or using a physical device to identify and resolve touch-related issues. - Leverage viewport meta tags to control how the web page is displayed on mobile devices, optimizing the viewport and scaling. Debugging Tip Learnings Section 4
16. Workspaces, snippets… Advanced Features Section 5
17. • The Workspaces feature allows you to map local project files to the web application, enabling real-time editing of source code directly within Chrome DevTools. • Link your project directory to Chrome DevTools to establish a bi-directional connection for seamless editing and synchronization. • Use Ctrl+O or Cmd+O to quick open a source file. Workspaces Section 5
18. • Chrome DevTools' Snippets feature lets you save and execute custom JavaScript code snippets directly within the Console panel. • Save frequently used code snippets for quick access and reuse during development tasks. Snippets Section 5
19. • Use the "Lighthouse" panel in Chrome DevTools to perform performance audits for your web applications. • Identify opportunities for performance improvements and receive suggestions to optimize loading times and user experiences. Lighthouse Section 5
20. - Chrome DevTools can be customized to fit your specific workflow and preferences. - Adjust panel layouts, change themes, and rearrange panels to create a personalized development environment. - Chrome DevTools often introduces experimental features that provide early access to cutting-edge functionalities. - Explore and enable experimental features from the "Experiments" section in the settings to test new capabilities. Customizing DevTools Experimental Features Extras… Section 5
21. “The most effective debugging tool is still careful thought, coupled with judiciously placed print statements.” Douglas Crockford
22. Thank You Usman Ogunsola Software Engineer twitter.com/unsaiddev github.com/ogunsoladebayo