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My static site (plain HTML/CSS/JS with jQuery 3.6 and a Swiper-powered slider) picked up two bugs after I added new pages. The homepage slider no longer auto-rotates—it loads the first slide and freezes until the manual arrows are clicked—and the hamburger menu on mobile opens but will not close unless the page is refreshed. A console read-out shows “Uncaught TypeError: Cannot read properties of null.” I will give you the GitHub repo plus a live preview link. I only need the underlying JavaScript/CSS conflicts resolved; no design or layout changes. Scope of work • Restore automatic rotation of the Swiper slider (it runs on the default settings—nothing custom). • Make the mobile navigation toggle open and close as expected. • Test and confirm the fixes on the last two versions of Chrome and Safari, both on desktop and on real iOS and Android devices. Deliverables 1. Updated code (pull request or zipped files) ready to drop back into the site. 2. A brief note outlining what you found and how you fixed it so I can learn from the issue. That’s it—two quick bug fixes, fully tested and documented.
Project ID: 40694232
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Hi, I've fixed this exact bug on template sites before, and it's usually a quick one. My guess: after you added the new pages, the script started running on pages where the slider or menu doesn't exist. That's what Cannot read properties of null means — the script looks for an element, doesn't find it, and stops right there. Everything after that line, including your auto-rotate and the menu close handler, never runs. I'll confirm as soon as I see the console and the repo. What I'll do: Reproduce both bugs on your preview link Fix the root cause, not just patch the symptom Test on Chrome + Safari, mobile and desktop Send a short note explaining what broke Fast and clean. No redesign, no rewriting your template, no extra libraries — I'll touch only the lines that need fixing, so nothing else on the site changes. $30 fixed works for me. 2 days, but I expect to be done sooner. Just send me the preview link — that's all I need to start. I'll look at the console and reply within the hour telling you exactly what's broken, before you commit to anything. If I'm wrong about the cause, you'll know right away and you've lost nothing. If I'm right, award the project and you'll have both fixes working by tomorrow morning. Thanks, Daniel.
$20 USD in 1 day
0.6
0.6
92 freelancers are bidding on average $28 USD for this job

The Swiper autoplay stopping after new pages were added, plus a mobile menu that opens but won’t close, usually points to one shared JS error breaking execution further down the file. That “Cannot read properties of null” message is the right place to start, because one missing selector or script load-order conflict can easily knock out both behaviors. I’d trace that first, fix the conflict cleanly, then test the slider and nav toggle across the environments you listed. I’ve handled this kind of front-end debugging on plain HTML/CSS/JS sites many times, including Swiper issues, jQuery conflicts, and mobile navigation scripts that fail after page additions or DOM changes. Since you only want the underlying code corrected and documented, the work stays focused with no unnecessary redesign touches. - Is the menu toggle and slider logic loaded from one shared JS file, or are they split across separate files? - Would you prefer the final delivery as a pull request to the repo, or updated files you can drop in directly?
$20 USD in 7 days
9.7
9.7

Hi there, I can quickly fix the Swiper auto-rotation and mobile menu issues without changing your design. I’ll trace the “Cannot read properties of null” error, identify the JS/CSS conflicts introduced by the new pages, and apply clean fixes to the existing jQuery/Swiper code. I’ll test across Chrome, Safari, iOS, and Android, then provide the updated files/PR with a brief explanation of the fixes. I can start immediately.
$20 USD in 1 day
9.1
9.1

Hello, My name is Yasir Shah, and as the founder of A4Logic, I've got over 15 years of experience in web development, making me a seasoned professional in fixing issues just like yours. I've successfully built high-quality web, mobile, AI, and automation solutions for numerous startups and businesses using the same technologies underpinning your site - HTML/CSS/JS with jQuery and Swiper-powered slider. Aside from my strong grasp on these core skills (CSS, Frontend Development, HTML, JavaScript), which align perfectly for resolving your issues, I possess deep knowledge in Python, PHP, API integrations and mobile apps (Flutter). This diverse skill set enables me to think outside the box to pinpoint where the bug lies and offer long-term solutions. My commitment extends beyond fixing bugs, I also ensure that my clients understand what went wrong and how I fixed it so that you can navigate similar difficulties in the future with confidence. At A4Logic we're not just focused on quick fixes; we're committed to delivering sustainable results. From my incredible problem-solving ability to my dedication to client satisfaction, you can trust that I'll get your site back up and running smoothly. Let's create a better browsing experience for your users by resolving these issues effectively and efficiently! Thanks!
$30 USD in 1 day
8.5
8.5

Hi, I can fix both issues without changing the existing design or layout. I’d first trace the “Cannot read properties of null” error and check for conflicts introduced by the new pages, then verify the Swiper initialization and mobile navigation event handling. For the slider, I’ll restore the default automatic rotation and make sure it continues working without affecting the manual controls. For the hamburger menu, I’ll fix the open/close behavior and check that the JavaScript and CSS states remain consistent. I’ll test the fixes across the requested Chrome and Safari versions, including real iOS and Android devices, and provide the updated code along with a short explanation of what caused each issue and how it was resolved. Best, Ivane
$20 USD in 7 days
8.4
8.4

Hello, I can see the hidden issue here: the slider and mobile menu are both breaking from a JavaScript state conflict, not from design changes. I’ve fixed many plain HTML/CSS/JS sites where one null reference quietly stops Swiper autoplay or leaves a hamburger toggle stuck open, and I’ll trace the exact conflict in your repo and preview link. I’ll inspect the script load order, event bindings, and any DOM selector mismatches causing “Cannot read properties of null,” then repair the slider autoplay and mobile nav behavior without touching the layout. I’ve shared an initial estimate based on your description, and once we go over a few technical or functional details, I’ll confirm the exact cost and delivery schedule. I can also verify the fix in Chrome, Safari, iOS, and Android, then return updated files plus a short note explaining what was wrong and how it was corrected. Could you share the GitHub repo and tell me whether the menu script or Swiper code was changed when the new pages were added? Looking forward to your reply so we can finalize the exact plan. Thanks, Asad
$30 USD in 3 days
8.1
8.1

That Uncaught TypeError is almost certainly a null reference triggered by your recent page additions—likely a missing DOM element or conflicting initialization order that broke both your Swiper-powered slider and your mobile navigation toggle. My core stack includes HTML, CSS, PHP, JavaScript, and jQuery, so I can go beyond templates and dive straight into your static site's underlying code to find the conflict. I will restore the automatic rotation of the Swiper slider, get the hamburger menu opening and closing as expected, and test everything across Chrome, Safari, and real iOS and Android devices. Along with the updated files, I will include a brief note outlining what went wrong and how I fixed it so you can learn from the issue. My bid is $30, delivery 1 days. Share the GitHub repo and live preview link, and I can get this sorted out right away.
$30 USD in 1 day
8.1
8.1

I’ll trace the “Cannot read properties of null” path first, then inspect the Swiper initialization and mobile menu selectors/event handlers. I’ll check for script-order issues, duplicated IDs, or newly added page elements causing the null reference, while keeping the existing HTML structure, styling, and default Swiper behavior unchanged. Within 1 day, I’ll return a clean pull request or zip containing the JavaScript/CSS fixes, plus a brief explanation of the root cause and changes. I’ll verify slider autoplay and menu closing on the last two Chrome and Safari versions across desktop, real iOS, and Android devices. Is the GitHub repo already showing the same null error as the live preview? Muhammad Saad
$30 USD in 1 day
7.8
7.8

Both symptoms point at one cause: that "Cannot read properties of null" is a script running before its element exists, and when it throws, every line after it in the same file never executes — which is exactly why the hamburger's close handler never binds and autoplay never starts. Most likely your new pages don't contain a selector the shared JS still queries, so I'd trace the exact throwing line from the stack trace, guard the element lookups, and make sure the nav toggle and Swiper init are independent rather than sharing a failure path. Then I'd confirm autoplay is actually configured with a delay and not being killed by a duplicate init from the new page includes. Tested on current Chrome and Safari, desktop plus real iOS and Android, delivered as a pull request with a short note explaining exactly what broke and why. I can start immediately — just send the repo link.
$10 USD in 1 day
7.9
7.9

A null-reference error after adding pages often means one selector is now missing on some templates, and that can stop the rest of the JavaScript from running. In your case, that would explain why Swiper loads the first slide but autoplay never kicks in, and why the hamburger menu opens once but won’t complete the close behavior properly. I’d isolate the exact failing line, patch the JS/CSS interaction cleanly, and verify the fixes on the browsers and devices you mentioned. Most quick fixes like this are not really about Swiper itself—they’re about script timing, duplicated handlers, or code trying to bind against elements that aren’t present on every page. I work on these front-end conflict fixes regularly and can keep the scope tight: repair, test, and leave you a short explanation of the root cause. - Did these issues begin immediately after the new pages went live, or were any shared header/footer files also changed? - Should I return the fix as a PR on GitHub, or do you want a zip with the corrected files and notes?
$18 USD in 7 days
7.9
7.9

I can fix the slider and mobile menu bugs on your static site. With 7+ years of web development experience, I will investigate the JavaScript console error, resolve the underlying conflicts, and ensure the mobile navigation and Swiper slider function as expected. I will provide the updated code and documentation on the findings once the testing across Chrome and Safari is complete. Regards, Ajhar
$20 USD in 7 days
7.6
7.6

I can quickly diagnose and fix the Swiper auto-rotation and mobile navigation toggle issues without changing your existing design or layout. I’ll trace the “null” error, resolve the JS/CSS conflicts, test across Chrome, Safari, iOS, and Android, and provide clean updated code with a brief fix summary. Best regards, Ihtsham
$20 USD in 1 day
7.2
7.2

Your two bugs look connected rather than separate: one JavaScript error is likely interrupting everything after the first failing call, which is why the slider freezes and the mobile nav doesn’t complete its toggle cycle. The fastest way to solve this is to check the failing selector, confirm whether the new pages changed the DOM structure, and then harden the script so it only runs where the needed elements exist. I’ve fixed similar issues on static sites using jQuery, Swiper, and shared navigation scripts where adding pages introduced null errors or event conflicts. Because you only need code-level corrections, testing, and a brief write-up, I’d keep the work focused and easy to review. - Are the new pages reusing the same header and script includes as the homepage? - For device testing, do you want a short checklist of what was verified on desktop and mobile along with the fix note?
$15 USD in 7 days
7.3
7.3

Hi, I went through your project details and understand what you're looking to achieve. I'd be interested in working with you on this. Based on the requirements you've shared, I can handle the project from start to completion while keeping the work aligned with your expectations, timeline, and desired outcome. My approach is straightforward: first, I'll make sure the requirements and expected deliverables are clear. Then I'll complete the work in structured stages, share progress along the way, incorporate your feedback, and deliver the final work after everything has been reviewed. Before we begin, I have a couple of questions about your requirements that will help me understand the scope more accurately. Feel free to message me so we can discuss the details and determine the best way to move forward. Best regards, Anum
$90 USD in 1 day
6.7
6.7

Hi, I can help you with those two bugs. The null error you're seeing is almost certainly a script trying to touch an element that doesn't exist on the new pages, which then kills the Swiper init and the menu toggle logic that runs after it. That's why the slider freezes and the hamburger won't close. I'm Edward, been doing front-end JS fixes like this for years. I'd clone your repo, reproduce both issues, patch the conflict, and test on the browsers and devices you listed. I can also leave you a clear note on what was breaking so you'll know for next time. Happy to chat if you want to get started.
$10 USD in 7 days
6.9
6.9

Hello I'll dive into your GitHub repo immediately to diagnose and fix the "Uncaught TypeError" causing your Swiper slider and hamburger menu issues. My extensive experience with jQuery and front-end debugging ensures I can quickly pinpoint the conflict introduced by the new pages. I'm confident I can restore your site's functionality efficiently. Would you like to discuss the specific timeline for this repair? Best regards, Giáp Văn Hưng
$25 USD in 7 days
7.0
7.0

Hi, Kindly share your website url, I will fix this issue right now. Ping me back so we can discuss it further and start asap. Regards, Nabeel Abid
$20 USD in 1 day
6.6
6.6

I can fix both issues without changing the site design: trace the null-reference error, restore Swiper autoplay, and correct the mobile menu toggle so it opens and closes reliably. I’ll test the fixes across recent Chrome and Safari on desktop and mobile, then deliver the updated code with a short note explaining the root cause and changes made.
$39 USD in 1 day
6.4
6.4

Hi, I'm Denis, a full-stack developer specializing in frontend bugs, particularly jQuery interactions and third-party libraries like Swiper. I've debugged similar issues where new page additions broke existing functionality. Your "Cannot read properties of null" error suggests the hamburger menu selector isn't finding its DOM element—likely due to HTML structure changes or scripts running before the element exists. The Swiper auto-rotation freeze typically indicates conflicting JavaScript from newly added pages interrupting initialization. I've resolved comparable projects where adding content broke jQuery and Swiper setups through duplicate script loading, selector conflicts, or initialization order issues. My approach: I'll review your repo and live site, inspect the browser console and network tab to pinpoint errors, then identify conflicting code—whether selector mismatches, duplicate initialization, or script loading order. I'll fix it directly and test thoroughly across Chrome, Safari, iOS, and Android to confirm both slider auto-rotation and menu toggle work consistently. The core fix involves ensuring Swiper initializes once with the correct DOM reference and your hamburger menu selector targets the right element regardless of structure changes. I'll document what caused each issue and how the fix works for future reference. I can start immediately. Let's connect and discuss. Thanks, Denis.
$30 USD in 1 day
6.2
6.2

Hey, The null TypeError is a useful starting point because the two failures appeared after new pages were added, which strongly suggests a missing element or script initialisation conflict rather than two unrelated UI bugs. I would trace the failing selector and initialization order first, then check how the Swiper instance and mobile menu handlers behave on pages where their expected elements are absent. I would keep the fix strictly within the existing HTML/CSS/JS and jQuery structure, restore the default Swiper autoplay, and make the navigation toggle safely handle both open and close states without changing the design. I would then verify the affected flows across the requested Chrome and Safari versions and real iOS and Android devices, with the PR or updated files accompanied by a concise explanation of the root cause. Can you provide the GitHub repository and live preview so I can reproduce the error before changing anything?
$250 USD in 5 days
5.9
5.9

hello, these are probably not two bugs. a single uncaught TypeError halts the rest of that script block, so everything registered after the failing line silently never runs. if your Swiper init and your menu toggle live in the same file, one null reference explains both symptoms at once, and it explains why two unrelated features stopped working on the same day you added pages. the usual cause is a shared script querying an element that exists on the homepage but not on the new ones, or the reverse. so the first move is finding which line throws and on which page, not fixing the slider and the menu separately. worth knowing about Swiper specifically, autoplay is not part of the default configuration. so if the slider genuinely ran on defaults and used to rotate, either an autoplay option got lost or the module is not registered in the build you are loading, which is a separate check. the fix i would make guards each init on its own element existing, so a script shared across pages stops breaking every time you add one. that is the part worth documenting for you. does the error appear on every page or only some? did the Swiper version or the way scripts are included change when you added the pages? have a nice day.
$90 USD in 1 day
6.0
6.0

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