no-deprecated-future-experimental-storage

Disallow the deprecated future.experimental_storage config and prefer top-level storage.

Targeted pattern scope

This rule focuses on docusaurus.config.* files.

It reports the deprecated 3.10-era migration source:

future.experimental_storage

and expects the stable replacement:

top-level storage

What this rule reports

This rule reports deprecated experimental storage config so sites can migrate to the stable storage field introduced in Docusaurus 3.10.

Why this rule exists

Docusaurus 3.10 promoted browser storage config out of the future object into the stable top-level storage field.

Keeping the deprecated experimental field around makes the config look newer than it really is and increases future upgrade noise.

❌ Incorrect

export default {
    future: {
        experimental_storage: {
            type: "localStorage",
            namespace: true,
        },
    },
};

✅ Correct

export default {
    storage: {
        type: "localStorage",
        namespace: true,
    },
};

Behavior and migration notes

This rule autofixes the simple cases it can prove safely:

replace a future object that only contains experimental_storage
remove experimental_storage from a larger future object and insert a top-level storage field when no top-level storage already exists

ESLint flat config example

import docusaurus2 from "eslint-plugin-docusaurus-2";

export default [docusaurus2.configs.recommended];

When not to use it

Do not use this rule only if you intentionally preserve the deprecated field during a short-lived migration and do not want linting to rewrite it yet.

Rule catalog ID: R107

Targeted pattern scope​

What this rule reports​

Why this rule exists​

❌ Incorrect​

✅ Correct​

Behavior and migration notes​

ESLint flat config example​

When not to use it​

Further reading​