Users are encountering a validation error in Shopify’s Theme Editor (Dawn theme) stating “Setting ‘margin_sides’ can’t be less than 0,” which prevents any theme changes from being saved.
Root Cause Identified:
The Instafeed app block is setting a default margin_sides value of -50, triggering the error
This appears to be a recent change in the app that affects theme functionality
Workaround Solutions:
Locate the margin_sides setting in template JSON files and manually change the value from -50 to 0
Use Shopify CLI (shopify theme pull) to download theme files and search across all files for the erroneous setting
If the setting isn’t visible, save the theme after encountering the error to make it appear in template files
Temporarily remove the Instafeed app block from pages to restore theme editing capability
Key Notes:
The issue affects both current and previously exported theme versions
Other app blocks may cause similar problems
Multiple users confirmed removing Instafeed immediately resolved the issue
Summarized with AI on October 29.
AI used: claude-sonnet-4-5-20250929.
This random error pops up in my Theme Editor (Dawn 15.3.0): “Setting ‘margin_sides’ can’t be less than 0”
I have not made any changes, and everything has worked well until now. I tried to simply change a header! Older versions (downloaded theme files) throw the same error, despite having been working just fine at the time of export. I only export bug-free themes as back-ups.
None of the custom CSS sets “margin_sides” to below 0. I have no idea where this error is coming from or where to make changes. Especially because this error has never occurred before.
Actually, I realise that I’ve been working with Dawn 15.0.0. Do updates get automatically installed or do I have to initiate them? Could this be due to an update from 15.0.0 to 15.3.0 and if yes is there a way to reverse it?!
Annoying as I can not update anything in my shop right now! Please help!
There is no built in feature to reverse it’s version from new one to old one. But while updating a theme shopify automatically make the duplication of the theme that you are going to update it. So you can use it. But if you facing the issue with margin this can be happen with the customization. So you can consider checking the margin value even you don’t touch the margin. Or you can get help from me.
Do you happen to have an “Instafeed” app block configured in your theme? We had this exact issue just today and found that it was due to the instafeed app block settings adding a default value of -50 in the margin_sides setting. You need to find that setting in your template json file and set it to 0 instead. I actually pulled down our live theme (“shopify theme pull” with shopify CLI) and searched for this settings across all theme files to find and fix all instances.
Note: If you can’t see the setting in your theme files, you possibly need to first save the the theme after seeing the error. That will make the erroneous settings appear in the theme template files such that you can then go and fix them. I hope that makes sense.
They must’ve made a change in their app to cause this. Pity it stops you from updating your theme completely. If you don’t have Instafeed then consider then it might be another app block doing exactly the same thing.
We we’re having this exact issue, and we spent hours trying to find the culprit, we have a lot of custom liquid sections, so we thought it must have been something we created, but after seeing this, we removed the instafeed app from our home page and it instantly fixed the issue! THANK YOU for commenting!