Fatal error: Uncaught Error: Call to undefined function register_widget()

Hello, I get this error:

Fatal error: Uncaught Error: Call to undefined function register_widget() in /home/innerspaoi/www/wp-includes/widgets.php:1730 Stack trace: #0 /home/innerspaoi/www/wp-includes/class-wp-hook.php(287): wp_widgets_init(”) #1 /home/innerspaoi/www/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array) #2 /home/innerspaoi/www/wp-includes/plugin.php(478): WP_Hook->do_action(Array) #3 /home/innerspaoi/www/wp-settings.php(546): do_action(‘init’) #4 /home/innerspaoi/www/wp-config.php(110): require_once(‘/home/innerspao…’) #5 /home/innerspaoi/www/wp-load.php(37): require_once(‘/home/innerspao…’) #6 /home/innerspaoi/www/wp-blog-header.php(13): require_once(‘/home/innerspao…’) #7 /home/innerspaoi/www/index.php(17): require(‘/home/innerspao…’) #8 {main} thrown in /home/innerspaoi/www/wp-includes/widgets.php on line 1730

I tried many times to reinstall wordpress, I used the console or even reinstalled manually the latest version by uploading manually the files.
I tried also to deactivate every plugin and theme, with no success and I only managed to fix this by re-uploading the widgets.php file in : www/wp-includes/widgets.php

Everytime I fix this, it just stays 1 day error free and I get again that fatal error

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