Shopify Admin Panel and Theme Customization Extremely Slow

[Emonx24]

ello everyone,

I’m facing a frustrating issue with my Shopify store. Despite having a high-speed internet connection (700-800 Mbps), my Shopify admin panel is running very slow. Even more, when I try to customize my theme, the changes take several minutes to save. Sometimes, it even takes 5-10 minutes for a section design to save.

I have tried switching between different browsers (Chrome, Firefox, Edge, Brave), but the issue persists on all of them. I’ve also checked my internet speed (via speedtest.net), and it’s working fine.

Has anyone else faced similar issues or have any suggestions on how to fix this? I’ve also tried clearing the cache and disabling browser extensions, but the issue remains unresolved.

Looking forward to any help or suggestions from the community. Thank you!

[mageplaza-cs]

Hi @Emonx24 

I am from Mageplaza - Shopify solution expert.

You're not alone—performance issues in the Shopify admin panel and theme customizer can be frustrating, and they aren’t always caused by your internet connection or browser. Here are some of the most common causes and solutions based on what others in the community and developers have experienced:

1. Theme Bloat or Poor Code Quality
Cause: If you're using a third-party theme or have heavily customized it, bloated Liquid templates, excessive JavaScript, or large image files can slow down the theme editor.

Fixes:

• Try switching to a Shopify default theme (like Dawn) and test if customization is faster.
• Audit your theme:
  Remove unused sections, blocks, or apps injecting code.
  Compress large images.
  Minify or defer non-critical JS/CSS.
• Use Shopify Theme Inspector for Chrome to debug slow sections.

2. Installed Apps Injecting Scripts
Cause: Some apps (especially older ones or those not optimized) inject a lot of scripts into your theme and admin experience.

Fixes:

• Disable or remove unused apps, especially ones related to design, tracking, popups, or page builders.
• Use the Shopify Admin -> Settings -> Apps and sales channels to disable and test.
• Contact app developers if you suspect an app is causing slowdown.

3. Browser or Machine Issues (even if you checked)
Double-check:

• Try running in Incognito/Private mode (to isolate extensions and caching).
• Test on another device and network (e.g., a phone on cellular) to rule out deeper network/machine issues.

4. Shopify Server Issues
Cause: Sometimes the issue is on Shopify's side—server lag, regional CDN issues, or account-specific glitches.

Fixes:

• Check Shopify Status Page for known outages.
• If this has been ongoing for more than a day or two, contact Shopify Support and provide:
  Store URL
  Time of issue
  Screenshots or screen recording
  Network logs (you can use Chrome DevTools -> Network tab)

5. Large Number of Metafields or Complex Theme Logic
Cause: Too many dynamic metafields or conditional logic in your theme can significantly slow down both frontend and the theme customizer.

Fixes:

• Simplify conditional rendering in templates.
• If you use metafields extensively, try to cache computed values when possible.

6. Custom Apps or APIs Overloading Store
Cause: Any private/custom app making frequent API calls (especially Admin GraphQL) can slow down the Admin panel.

Fix:

• Check your Shopify API Call Limits in the custom app logs.
• Temporarily disable custom integrations to test.

Please let me know if it works as expected!

Best regards!