7 minute read

Let’s consider a scenario that just might be all too familiar to you. Your team is just a few moments away from the most awaited product launch. Everything is set! Your design team has aced it with a pixel-perfect UI, product managers have never been more confident in the features, and the marketing team has really gone out of its way to get everyone hyped up about the release. But the dreaded thing shows its ugly head! Just as the QA team begins cross-browser testing, critical issues start surfacing—buttons misaligned on the browser, form validation failing on specific Android devices, and unexpected layout glitches on tablets. Gutting, to say the least!

If you are an experienced Front-End Developer, UI/UX Designer, or Quality Analyst, these last-minute bugs would be no stranger to you at all. You most certainly know that such bugs have the potential to derail even the most meticulously planned projects, and you understand well that addressing them goes far beyond the technicalities of fixing glitches. It is now more about protecting your product’s reputation and ensuring a seamless experience for users across platforms. A 2021 Tricentis study found that organizations with mature testing practices experienced a 30% reduction in software defects, further highlighting the importance of identifying and addressing front-end bugs early in the development process.

It certainly could be unnerving. However, this list of the top 10 front-end bugs, their causes, and actionable fixes can help you manage them effectively. It can equip your team to tackle them efficiently and confidently.

What are the Top 10 Front-End Bugs Encountered?

1. Cross-Browser Compatibility Issues

The Problem

A Statista study showed a significant market share for various browsers: Chrome (60-70%), Safari (15-20%), Edge (5-10%), and Firefox (5-10%). A web page that looks and feels perfect in Chrome may break in Safari or Edge – thanks to the variations in how browsers render HTML, CSS, and JavaScript. Clearly, its not a one–size-fits-all. This diversity only further underscores the crucial need for cross-browser compatibility testing to ensure a consistent user experience across all platforms.

How to fix it?

  • Use relevant tools to check feature compatibility.
  • Use polyfills and vendor-specific prefixes for unsupported features.
  • Ensure a consistent experience by conducting comprehensive UI UX testing with the use of platforms like BrowserStack.

2. Responsive Design Breakpoints

The Problem

A number of studies have shown that first impressions are of great significance, and these are primarily influenced by web design. About 94% of users’ initial judgments of sites are based on their visual appearance. Poor design and content can hinder a significant portion of visitors to the extent of causing about 38% of them to navigate away from the site. This underscores the critical need for responsive design, ensuring optimal user experience across various devices and screen sizes. Layout issues, such as breaks or misalignments, in particular, impact usability on tablets and smartphones.

How to fix it?

  • Be sure to define breakpoints that are aligned with popular device resolutions.
  • Use relative units like em, rem, or percentages for scaling.
  • Leverage modern layout systems like CSS Grid or Flexbox for responsive designs.

3. Broken UI Components

The Problem

Frustrated and disrupted workflows as a result of unexpected glitches in the functionality of buttons, modals, or dropdowns.

How to fix it?

  • Identify missing event listeners or DOM structure issues with the use of debugging tools like Chrome DevTools.
  • Test components thoroughly with realistic and edge-case scenarios.
  • Ensure proper binding of event listeners and clear error handling in component logic.

4. JavaScript Errors

The Problem

One study found that 68% of JavaScript errors are related to DOM interactions, highlighting the importance of robust error handling and careful DOM manipulation. Uncaught exceptions, undefined variables, or unhandled promises lead to broken functionality, resulting in significant repercussions for teams. 

How to fix it?

  • Use ESLint or similar tools to catch syntax errors and enforce coding standards.
  • Implement try-catch blocks for error handling and Promise handlers for async calls.
  • Debug scripts with browser developer tools and monitor logs for anomalies.

5. Performance Issues

The Problem

According to Google’s research, a one-second increase in page load time shows a correlation with a 7% reduction in conversion rates. Optimizing performance is critical for user engagement and business success. Slow page loads, unresponsive interfaces, and high resource usage result in highly frustrated users and impact retention.

How to fix it?

  • Utilize formats like WebP and enable lazy loading to optimize images.
  • Reduce JavaScript bundle sizes by using code-splitting and minification.
  • Measure performance with tools like Google Lighthouse and implement recommendations.

6. Form Validation Failures

The Problem

Incorrect form submissions or lack of error feedback resulting in poor user experiences.

How to fix it?

  • Make use of native HTML5 validation attributes like required and pattern.
  • Use libraries like Formik or custom JavaScript logic to enhance client-side validation.
  • Provide clear error messages and visual cues to guide users.

7. Caching Problems

The Problem

Did you know that in roughly about 50% of cases, mobile users are accessing information from a cache that could be as old as 12 hours? Cached assets result in users seeing outdated content or encountering unexpected behaviour, making it essential for teams to ensure effective caching strategies in optimizing page load times and improving user experience, especially on mobile devices.

How to fix it?

  • Implement cache-busting techniques, such as appending version hashes to asset filenames.
  • Employ service workers to implement sophisticated caching mechanisms, such as caching frequently accessed resources and selectively updating cached content within your PWAs.
  • Ensure updated content delivery by properly configuring Cache-Control headers.

8. API Integration Failures

The Problem

In a significant prediction, McKinsey emphasized that the number of APIs deployed in banking will increase by 100% from 2022 to 2027. With the growing reliance on APIs, robust integration testing and error handling are essential for ensuring application stability and reliability. 

Parts of the application are rendered unusable as a result of incorrect or missing data.

How to fix it?

  • Use tools like Postman to validate API responses before integration.
  • Implement fallback states for failed or delayed API calls.
  • Identify integration issues early with the use of proper error logging and monitoring tools.

9. Accessibility Oversights

The Problem

Inaccessible navigation, missing ARIA attributes, or low-contrast designs exclude users with disabilities. A 2024 report revealed that the average number of accessibility errors per home page was 56.8, and the most common web accessibility error is low-contrast text, which affects 83% of web pages with text.

How to fix it?

  • Use tools like Axe or WAVE to audit accessibility.
  • Follow the WCAG guidelines for compliant design and coding.
  • Regularly test your application with screen readers and keyboard navigation.

10. Memory Leaks

The Problem

Applications slow down or crash after extended use, especially on lower-end devices.

How to fix it?

  • Profile memory usage using browser developer tools.
  • Ensure cleanup of unused DOM elements and event listeners.
  • Optimize state management by reducing unnecessary re-renders in frameworks like React or Vue.

How Does Bugasura Help Simplify Bug Tracking?

There is no doubt that managing front-end bugs can be a complex feat. However, tools like Bugasura have been incredible in simplifying the process with its features such as:

  1. Centralized Bug Management whereby all reported issues can be tracked and managed in a unified dashboard.
  2. Cross-Browser Testing that allows teams to identify browser-specific bugs quickly with seamless integration tools.
  3. Real-Time Collaboration that enables clear communication between developers, QA, and designers with tagging and commenting features.
  4. Actionable Analytics providing teams with insights into recurring bug patterns, resolution timelines, and team productivity.

Customizable Workflows that allow teams to adapt the bug resolution process to suit their project’s unique needs.

With such features, Bugasura’s bug-tracking software is the perfect partner to streamline your bug-tracking process, helping your team deliver flawless front ends with absolute confidence.

Integrating Bugasura into your workflow can help your team enhance bug tracking, streamline collaboration, and deliver polished, bug-free products that delight users.

Are you ready to elevate your front-end testing process with Bugasura’s bug-tracking tool? 

What are you waiting for?

Explore today

Frequently Asked Questions:

1. What are the most common causes of cross-browser compatibility issues?

Different Rendering Engines: Browsers use different rendering engines (e.g., Blink, WebKit, Gecko) to interpret and display HTML, CSS, and JavaScript. This can lead to variations in how elements are styled, positioned, and behave.
CSS Quirks Mode: Older or poorly coded HTML can trigger quirks mode in some browsers, leading to unexpected rendering behavior.
JavaScript Incompatibilities: Different JavaScript engines may handle certain features or syntax differently, causing errors or unexpected behavior.

2. How can I effectively test for responsive design breakpoints?

Use browser developer tools: Resize the browser window manually to simulate different screen sizes and observe how the layout adapts.
Utilize responsive testing tools: Tools like BrowserStack or LambdaTest allow you to test your website on a wide range of devices and screen sizes.
Consider using a responsive design testing framework: Frameworks like RWD Test can help automate responsive testing and identify potential issues.

3. What are some common causes of JavaScript errors?

Syntax errors: Typos, missing semicolons, or incorrect use of operators.
Reference errors: Trying to access a variable or object that doesn’t exist.
Type errors: Using a value of the wrong data type (e.g., trying to add a string to a number).
Unhandled exceptions: Errors that are not caught by try-catch blocks, leading to the application crashing.

4. How can I improve the performance of my website?

Optimize images: Use appropriate image formats (e.g., WebP, JPEG 2000), compress images, and implement lazy loading.
Minimize HTTP requests: Reduce the number of files that need to be downloaded by combining CSS and JavaScript files, using a content delivery network (CDN), and optimizing fonts.
Leverage browser caching: Set appropriate cache headers to allow browsers to store static assets locally.
Minimize JavaScript: Reduce the amount of JavaScript code executed on the page by using techniques like code splitting and tree shaking.

5. How can I ensure my website is accessible to users with disabilities?

Follow WCAG guidelines: The Web Content Accessibility Guidelines (WCAG) provide a set of technical standards for making web content accessible to people with disabilities.
Use ARIA attributes: ARIA attributes provide additional information about the role and state of UI elements to assistive technologies.
Test with assistive technologies: Use screen readers and keyboard navigation to test how your website is experienced by users with disabilities.

6. What are some common caching issues?

Outdated content: Cached versions of pages or assets may not reflect the latest updates.
Cache invalidation problems: Incorrectly configured cache headers can prevent browsers from updating cached content.
Browser caching inconsistencies: Different browsers may handle caching differently, leading to unexpected behavior.

7. How can I effectively test API integrations?

Use API testing tools: Tools like Postman can help you test API endpoints, simulate requests, and validate responses.
Mock APIs: Create mock APIs to simulate real-world API behavior and test integration logic without relying on external services.
Implement robust error handling: Handle potential API errors gracefully, such as network issues, server errors, or invalid responses.

8. What are the consequences of memory leaks in web applications?

Slow performance: As the application runs, memory leaks cause the browser to consume more and more memory, leading to slowdowns and eventually crashes.
Unresponsive user interface: Memory leaks can make the user interface unresponsive and sluggish.
Increased resource consumption: Memory leaks can impact the overall performance of the device, especially on mobile devices.

9. What are some common accessibility oversights in web design?

Low color contrast: Insufficient color contrast between text and background can be difficult for people with low vision to read.
Poor keyboard navigation: Elements may not be focusable or navigable using only the keyboard.
Missing alternative text for images: Screen readers cannot describe images without alternative text.

10. How can I debug front-end issues effectively?

Use browser developer tools: Browser developer tools provide a wealth of debugging features, including breakpoints, step-by-step execution, and inspecting the DOM and network traffic.
Console logging: Use console.log() to print messages to the browser console for debugging purposes.
Use a debugger: Step through your code line by line to identify the source of errors.
Inspect network requests: Analyze network requests to identify slow-loading resources or API errors.