matteocontrini very true because i had uninstalled Cloudflare long ago , so i got confused but still purge everything.
Inside
storage/logs there were no errors reported, i could have quote it.
Now the error surfaced
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use Flarum\Extend;
return [
new Blomstra\Redis\Extend\Redis([
'host' => '127.0.0.1',
'password' => null,
'port' => 6379,
'database' => 1,
])
];
its added in extend.php but not found
and immediately after adding this code, with or without the extension installed, it brings the http 500 error