{"id":19001495,"date":"2026-08-24T14:18:23","date_gmt":"2026-08-24T14:18:23","guid":{"rendered":"https:\/\/wordpress.org\/support\/topic\/freemius-compatibility-bug\/"},"modified":"2026-08-24T14:18:23","modified_gmt":"2026-08-24T14:18:23","slug":"freemius-compatibility-bug","status":"publish","type":"topic","link":"https:\/\/wordpress.org\/support\/topic\/freemius-compatibility-bug\/","title":{"rendered":"Freemius compatibility bug"},"content":{"rendered":"\n
AI describing the problem as I couldn't.

Bug Report: Freemius SDK permanently modifies active_plugins when Plugin Organizer filters the option


Date of confirmed incident: 2026-08-22 11:43:00 (site local time)

Symptom: Multiple plugins appear deactivated in wp-admin; files remain on disk; active_plugins in MySQL is shortened.

Executive summary

This is not a PHP fatal crash. Freemius\u2019s fs_newest_sdk_plugin_first() runs during normal WordPress bootstrap, calls get_option('active_plugins'), gets a filtered (short) list from Plugin Organizer, then update_option('active_plugins', \u2026) and writes that short list to the database. Plugins that were only hidden for the current URL look permanently deactivated.

Root cause: Freemius treats a filtered read as the canonical active list and persists it.

Amplifier: Plugin Organizer MU filters option_active_plugins per URL with no write-protection (Perfmatters MU documents the same Freemius risk and adds a guard; PO does not).

Environment

Component Version \/ notes

WordPress

WooCommerce store, ~64 active plugins

Plugin Organizer

10.2.5 + MU loader PluginOrganizerMU.class.php

Freemius SDK carriers on site

woo-coupon-usage-pro, post-smtp, 3d-viewer (each bundles Freemius)

Perfmatters MU

Has pre_update_option_active_plugins write guard; explicitly comments about Freemius

Object Cache Pro

Was disabled during testing; issue reproduced without Redis

Step-by-step: how plugins get \u201cdeactivated\u201d

Step 1 \u2014 Plugin Organizer hides plugins for this request only

Plugin Organizer MU hooks early:

PluginOrganizerMU.class.php

Lines 504-504

add_filter('option_active_plugins', array($PluginOrganizerMU, 'disable_plugins'), 1, 1);

For a given front-end URL, PO removes plugins from the in-memory list returned by get_option('active_plugins'). Those plugins are not loaded this request, but should still be active in the DB.

On our site, PO commonly hides ~5 plugins on product\/checkout URLs, including:

woo-order-export-lite

woocommerce-avatax

woocommerce-sendinblue-newsletter-subscription

woocommerce-advanced-bulk-edit

woocommerce-ajax-filters

Step 2 \u2014 WordPress boots on a normal front-end request

Any full WP bootstrap can trigger this: homepage \/, product pages, checkout, missing static files routed to index.php (e.g. .map 404s), etc.

Step 3 \u2014 Freemius loads during wp-settings.php

When Woo Coupon Usage Pro loads, Freemius start.php decides the SDK load order needs updating and calls:

start.php

Lines 258-260

if ( ! $fs_active_plugins->newest->in_activation ) {

\u00a0 \/\/ Re-order plugins to load this plugin first.

\u00a0 fs_newest_sdk_plugin_first();

(Post SMTP\u2019s copy of the same SDK provides the update_option frame in the backtrace below.)

Step 4 \u2014 Freemius reads filtered list, writes it to DB

fs-essential-functions.php

Lines 305-332

$active_plugins \u00a0 \u00a0 \u00a0 \u00a0 = get_option( 'active_plugins', array() );

$updated_active_plugins = array( $newest_sdk_plugin_path );

\/\/ ... reorder loop ...

if ( $plugin_found ) {

\u00a0 \u00a0 update_option( 'active_plugins', $updated_active_plugins );

\u00a0 \u00a0 return true;

}

Bug: get_option('active_plugins') returns PO\u2019s filtered list (~57 plugins), not the real DB list (~64). Freemius reorders that short list and update_option persists it. Plugins PO hid are dropped from MySQL permanently.

Step 5 \u2014 Site behavior after write

wp-admin \u2192 Plugins shows plugins as Inactive

Plugin files still exist

No PHP fatal in debug.log for this event

Restore requires manual re-activation or WP-CLI

Proof \u2014 primary log entry (2026-08-22 11:43:00)

Source: wp-content\/uploads\/XXXXX\/plugin-activation-changes.log (custom MU logger on update_option_active_plugins)

{

\u00a0 \"time\": \"2026-08-22 11:43:00\",

\u00a0 \"user_id\": 0,

\u00a0 \"username\": \"system\",

\u00a0 \"ip\": \"xx.xx.xx.xx\",

\u00a0 \"method\": \"GET\",

\u00a0 \"uri\": \"\/\",

\u00a0 \"referer\": \"\/wp-admin\/admin.php?page=post-smtp-pro\",

\u00a0 \"doing_cron\": false,

\u00a0 \"doing_ajax\": false,

\u00a0 \"is_cli\": false,

\u00a0 \"via\": \"update_option_active_plugins\",

\u00a0 \"old_count\": 57,

\u00a0 \"new_count\": 59,

\u00a0 \"added_count\": 2,

\u00a0 \"removed_count\": 0,

\u00a0 \"added\": [

\u00a0 \u00a0 \"woocommerce-gateway-amazon-payments-advanced\/woocommerce-gateway-amazon-payments-advanced.php\",

\u00a0 \u00a0 \"3d-viewer\/3d-viewer.php\"

\u00a0 ],

\u00a0 \"removed\": [],

\u00a0 \"backtrace\": [

\u00a0 \u00a0 \"update_option() wp-content\/plugins\/post-smtp\/freemius\/includes\/fs-essential-functions.php:332\",

\u00a0 \u00a0 \"fs_newest_sdk_plugin_first() wp-content\/plugins\/woo-coupon-usage-pro\/freemius\/start.php:260\",

\u00a0 \u00a0 \"require_once() wp-content\/plugins\/woo-coupon-usage-pro\/woo-coupon-usage.php:42\",

\u00a0 \u00a0 \"wcu_fs() wp-content\/plugins\/woo-coupon-usage-pro\/woo-coupon-usage.php:73\",

\u00a0 \u00a0 \"include_once() wp-settings.php:597\",

\u00a0 \u00a0 \"require_once() wp-config.php:113\",

\u00a0 \u00a0 \"require_once() wp-load.php:50\",

\u00a0 \u00a0 \"require_once() wp-blog-header.php:13\",

\u00a0 \u00a0 \"require() index.php:17\"

\u00a0 ]

}

How to read this entry

Field Meaning

user_id: 0 \/ username: system

Not wp-admin deactivate; automated write during bootstrap

uri: \/

Normal homepage request (not Plugins screen)

old_count: 57

Filtered count (PO hid ~7 plugins from the read)

new_count: 59

Written list still short vs true 64

removed: []

Logger compared filtered $old to filtered $new \u2014 missed the 5 dropped plugins

Backtrace

Freemius fs_newest_sdk_plugin_first() \u2192 update_option('active_plugins')

Proof \u2014 database impact (snapshot diff)

Before incident (\/tmp\/active-before-product.txt): 64 active plugins

After incident (wp plugin list --status=active): 59 active plugins

Plugins removed from DB (present before, missing after):

woo-order-export-lite

woocommerce-avatax

woocommerce-sendinblue-newsletter-subscription

woocommerce-advanced-bulk-edit

woocommerce-ajax-filters

These match Plugin Organizer\u2019s typical per-URL disabled set \u2014 not random corruption.

No PHP fatals during this test window in wp-content\/debug.log.

Proof \u2014 same bug on earlier dates (pattern)

Same mechanism, different URLs \u2014 all user_id: 0, no admin action:

Time \u00a0URI Logged change

2026-08-21 11:47:48

\/wp-content\/plugins\/post-smtp\/...\/party.min.js.map

added: [3d-viewer]

2026-08-21 12:38:03

\/

added: [amazon-payments-advanced, 3d-viewer]

2026-08-21 14:20:48

\/checkout\/order-pay\/...

added: [3d-viewer]

Example (Aug 21 \u2014 .map 404 bootstraps full WordPress):

SH_PLUGIN_CHANGE {\"time\":\"2026-08-21 11:47:48\",\"added\":[\"3d-viewer\/3d-viewer.php\"],\"removed\":[],\"user_id\":0,\"username\":\"system\",\"uri\":\"\/wp-content\/plugins\/post-smtp\/Postman\/Wizard\/assets\/js\/party.min.js.map\"}

The .map file does not exist; .htaccess sends the request to index.php \u2192 full WP load \u2192 Freemius runs.

Proof \u2014 Perfmatters already documents this Freemius behavior

Perfmatters MU explicitly guards against it:

perfmatters_mu.php

Lines 198-212

\u00a0* Plugins like Freemius call get_option( 'active_plugins' ) at include time

\u00a0* (while our read filter is still active), reorder the list, and update_option()

\u00a0* the result. Without this guard, MU-hidden plugins are permanently deactivated.

\u00a0*\/

function perfmatters_mu_protect_write($value) {

\u00a0 \u00a0 \/\/ ... merges hidden plugins back into the value before save ...

}

Plugin Organizer has the read filter but no equivalent write guard.

Affected parties & recommended fixes

1. Freemius (primary) \u2014 github.com\/Freemius\/wordpress-sdk

Issue: fs_newest_sdk_plugin_first() must not call update_option('active_plugins', \u2026) based on a filtered get_option().

Suggested fix:

Read unfiltered value (direct $wpdb, or temporarily remove all option_active_plugins filters), or

Only reorder if count\/set matches unfiltered DB, or

Use pre_update_option_active_plugins to merge back filtered-out plugins (Perfmatters pattern).

Carriers on our site: Coupon Usage Pro, Post SMTP, 3D Viewer \u2014 all use the same SDK function.

2. Plugin Organizer

Issue: Per-URL filtering is by design, but combined with Freemius it causes permanent deactivations.

Suggested fix: Add pre_update_option_active_plugins write protection (restore any plugins PO hid on that request), matching Perfmatters MU.

3. Plugin vendors using Freemius (Coupon Usage, Post SMTP, bPlugins\/3D Viewer)

Please escalate to Freemius and\/or ship a guard until SDK is fixed. Reproduction does not require your plugin\u2019s UI \u2014 only SDK bootstrap on a front-end request with PO active.

What this is NOT

Not malware or manual admin deactivation

Not Redis\/cache illusion (MySQL active_plugins was verified shortened)

Not caused by 3D viewer shortcode or .stl files (correlation only)

Not a PHP crash \u2014 silent option write; site may keep running with plugins missing

Reproduction steps (for vendors)

WordPress site with Plugin Organizer MU active and per-URL plugin disables configured

Multiple plugins using Freemius SDK (we have 3+)

Load any front-end URL that triggers PO filtering (homepage, product, checkout)

Condition: Freemius decides SDK reorder is needed (fs_newest_sdk_plugin_first() in backtrace)

Observe active_plugins option count drop in DB; wp-admin shows plugins Inactive

Verify:

wp plugin list --status=active --format=count \u00a0 # drops vs expected

wp option get active_plugins --format=json \u00a0 \u00a0 \u00a0# shorter array in DB

Hook logger on pre_update_option_active_plugins and log backtrace \u2014 expect fs_newest_sdk_plugin_first.

Workarounds (site operator)

Disable Plugin Organizer (and MU loader) until fixed

Keep Perfmatters MU write guard (helps for plugins Perfmatters hides, not PO\u2019s set)

Add site-wide pre_update_option_active_plugins guard that restores filtered plugins

Reduce Freemius carriers if possible

Monitor with plugin-activation-changes.log

Attachments we can provide on request

Full plugin-activation-changes.log

Before\/after active plugin name lists

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