"online store editor session can't be published" Message

Technical Q&A

Topic summary

Users encounter a “online store editor session can’t be published” error when attempting to save theme customizations in Shopify’s theme editor.

Initial Troubleshooting:

  • Standard browser-related fixes (clearing cache, incognito mode, different devices) typically don’t resolve the issue
  • Problem often persists across multiple users and devices

Root Causes Identified:

  1. JSON file size limitation: Shopify enforces a hidden ~1.5MB limit on theme JSON files. Accumulated content from blocks, sections, SVG codes, and custom CSS can exceed this threshold.

  2. Specific CSS properties: Several users report the error triggers when using:

    • content: "" in CSS pseudo-elements
    • !important declarations
    • Commented code lines in custom CSS
    • visibility: hidden; property

Working Solutions:

  • Delete unused sections, blocks, and custom code to reduce JSON file size
  • Move custom CSS to external files (theme.liquid or separate CSS files) instead of inline sections
  • Replace problematic CSS properties:
    • Use display: none; instead of visibility: hidden;
    • Use pointer-events: none; as alternative to pseudo-element strikethroughs
    • Remove !important declarations
    • Delete commented code lines
  • Use single quotes instead of double quotes in CSS (unconfirmed)

Status: No official fix from Shopify; issue remains ongoing across multiple theme versions (Dawn, Prestige).

Summarized with AI on October 27. AI used: claude-sonnet-4-5-20250929.
10

Hi @marley970.

I have found the problem and solution to that.

The problem is the limitation on the json file size in Shopify. So this means everytime that you write a code and this code combine some kind of content like links, SVG code, ect, this will add to the json file as well. So in time they sum up and take a space. Shopify put the hidden limit on the json file to max 1.5 MB. This means if you reach this limit, you are not be able to save any sassion any more because there is no more free space to use.

The solution is that:

  1. delete all the hidden section that you do not need

  2. with a developer delete all the blocks, codes, customized section, block and option that you do not need

  3. try to use less SVG codes and custom CSS

these above solution have solved our problem, and we are now freely continue developing our shop. I hope that would help you too

best,

Dr. Alex Lindt

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