# GrapesJSBuilder works for Email but not for Landing Pages

**URL:** <https://forum.mautic.org/t/grapesjsbuilder-works-for-email-but-not-for-landing-pages/36713>\
**Category:** Mautic 5 Install/Upgrade Support\
**Created:** [October 13, 2025, 4:35am UTC](https://forum.mautic.org/t/grapesjsbuilder-works-for-email-but-not-for-landing-pages/36713 "2025-10-13T04:35:44Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![jodywhitesides](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/jodywhitesides/32/12645_2.png) [@jodywhitesides](https://forum.mautic.org/u/jodywhitesides)\
**Post date:** [October 13, 2025, 4:35am UTC](https://forum.mautic.org/t/grapesjsbuilder-works-for-email-but-not-for-landing-pages/36713/1 "2025-10-13T04:35:44Z")

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**Your software**  
My Mautic version is: 5.1  
My PHP version is: 8.1  
My Database type and version is: mariadb operator 11.8.2-MariaDB-ubu2404

**Your problem**  
My problem is: Landing pages using GrapesJS builder fail to load with “Error: No valid HTML template found”. The builder interface shows a blank page instead of loading properly. Browser console shows 404 errors for: [https://mautic.mydomain.com/s/grapesjsbuilder/page/new\_[hash]?template=blank](https://mautic.mydomain.com/s/grapesjsbuilder/page/new_%5Bhash%5D?template=blank) However, the routes are registered as /s/s/grapesjsbuilder/ (with double /s/): - grapesjsbuilder\_upload: /s/s/grapesjsbuilder/upload - grapesjsbuilder\_delete: /s/s/grapesjsbuilder/delete - grapesjsbuilder\_assets: /s/s/grapesjsbuilder/assets - grapesjsbuilder\_builder: /s/s/grapesjsbuilder/{objectType}/{objectId} Manually accessing [Mautic](https://mautic.jodywhitesides.com/s/s/grapesjsbuilder/page/new?template=blank) DOES work and returns data. The GrapesJS plugin Config/config.php defines routes with ‘/s/grapesjsbuilder/’ prefix, but Mautic’s RouteLoader.php adds an additional ‘/s/’ prefix to all secure routes, resulting in ‘/s/s/grapesjsbuilder/’. Email builder with GrapesJS works fine - only landing pages are affected.

These errors are showing in the log:  
I’m not sure what log to find…

Steps I have tried to fix the problem:

1. Verified GrapesJS plugin is installed and enabled in database (plugins table shows is\_missing=0) 2. Cleared Mautic cache multiple times (php bin/console cache:clear) 3. Verified theme files exist (themes/blank/config.json and templates are present) 4. Checked routes with debug:router - routes show /s/s/grapesjsbuilder/ instead of /s/grapesjsbuilder/ 5. Attempted to remove /s/ prefix from plugin config.php paths - this broke Mautic completely 6. Modified JavaScript (builder.js) to generate /s/s/grapesjsbuilder/ URLs to match registered routes 7. Edited both source and compiled (dist/builder.js) JavaScript files 8. Cleared browser cache completely and tested in incognito mode 9. Verified blank theme config.json includes “builder”: [“legacy”, “grapesjsbuilder”] 10. Checked that #builder\_url field contains correct URL value 11. Confirmed the issue persists across different browsers The root cause appears to be a mismatch between: - JavaScript generating URLs with single /s/ prefix - Symfony routes registered with double /s/s/ prefix - Uncertainty about whether /s/s/ is intentional or a bug in route registration

**Needed:**  
Has anyone dealt with this? How has it be resolved to work correctly for both email and landing pages.

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**Author:** ![ricfreire](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/ricfreire/32/14973_2.png) [@ricfreire](https://forum.mautic.org/u/ricfreire)\
**Post date:** [October 13, 2025, 2:28pm UTC](https://forum.mautic.org/t/grapesjsbuilder-works-for-email-but-not-for-landing-pages/36713/2 "2025-10-13T14:28:04Z")

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Hello @jodywhitesides

Clarify one thing: Are you using standart Mautic Landing page templates or you installed your own template and it doesn’t work?

Best regards,  
Ricardo

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**Author:** ![jodywhitesides](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/jodywhitesides/32/12645_2.png) [@jodywhitesides](https://forum.mautic.org/u/jodywhitesides)\
**Post date:** [October 13, 2025, 4:54pm UTC](https://forum.mautic.org/t/grapesjsbuilder-works-for-email-but-not-for-landing-pages/36713/3 "2025-10-13T16:54:27Z")

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I’m using standard Mautic Landing Page template.

I finally figured out that Mautic is looking for /s/s/location and not /s/location like everywhere else.

Not sure where that came from.