Slate is NOT uploading settings_data.json (since I edited it with CMS) about slate HOT 3 OPEN

You're most likely running into an issue with incompatible schema in Shopify. Have you confirmed that your settings_data.json is valid by copy/pasting it into your theme files with the Admin GUI editor? I've run into cases where after making Section changes in the admin and then trying to upload the data file it will upload it but not save due to incompatible schema based on the section settings. Slate does not warn you about this, although ThemeKit I believe does in the same scenario.

from slate.

yes, I have confirmed that the settings_data.json is valid (and as I mentioned, I am able to upload it directly with themekit from the build directory)

from slate.

Could it be possible you forgot to modify your .env file? there is a default
SLATE_IGNORE_FILES=config/settings_data.json

Unfortunately slate looks like its uploading ignore files although it will not.

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