SharePoint list losing JSON formatting

Question

In SharePoint Online I add simple JSON sectioning to a list form. Preview looks fine and saving the JSON works, too.

But after closing the dialog and opening a list item, the formatting is lost.

Going back into the JSON dialog, it is empty.

The list has about 70 fields, but even with a simple JSON the error persists.

{
    "sections": [
        {
            "displayname": "Header",
            "fields": [
                "Title",
                "Description",
                "Introduction",
                "Priority"
            ]
        }
    ]
}

This are two screenshots: first the form after successfully adding the JSON and below after hitting CTRL+R.

Answer 1

In general, I would suggest after reviewing the JSON format code to make a copy of your formula and then paste it into any editor to allow rollback in case you get such unexpected behavior.

Regarding this unexpected behavior, there may be a problem with your browser cache, so try

• Clear browser cache
• Use Microsoft Edge in a private session and check if you get your formula back!

Finally, I would like to suggest

• Create a new list from scratch and check if you can apply your format code or not!
• If the problem persists, try opening a ticket with Microsoft Support, it could be a temporary problem!

Answer 2

"I have solved this by turning off the sync for the list in List Settings > Advanced Settings > Set Offline client availability to No."

See https://techcommunity.microsoft.com/t5/sharepoint/sharepoint-list-form-configure-layout-body-not-working/m-p/3183590/highlight/true#M57614