https://wpforo.com/community/how-to-and-troubleshooting-2/a-plugin-has-prevented-updates-by-disabling-wp_version_check/

Thank you

Please try to do this small change in core file. We'll update it in next release.

Open /wp-content/plugins/wpforo/wpf-includes/class-notices.php file.

Find this line:

if(!wpforo_is_session_started()) session_start();

Change to this:

if( !wpforo_is_session_started() && !is_admin() ) session_start();

Thank you Anonymous20,

Unfortunately the debug code says nothing new. The issue is general issue. All plugins who call session_start() function cannot be edited by WordPress editor, because the new version of WordPress editor tries to execute code to check if it doesn't returns any error. Other editors works fine, they don't try to execute the edited code. We'll check this and try remove session functions in dashboard.

I have done some reading about this. It seems that WP doesn't use php sessions at all. And there are many reasons not to use them, performance one of them. Or so i read.

Still. i'm not into programming, so ....

Unfortunately the debug code says nothing new. The issue is general issue. All plugins who call session_start() function cannot be edited by WordPress editor, because the new version of WordPress editor tries to execute code to check if it doesn't returns any error. Other editors works fine, they don't try to execute the edited code. We'll check this and try remove session functions in dashboard.

Starting edit check
Body:

Connection failed
WP_Error::__set_state(array(
'errors' =>
array (
'http_request_failed' =>
array (
0 => 'cURL error 28: Operation timed out after 100002 milliseconds with 0 bytes received',
),
),
'error_data' =>
array (
),
))

In most cases, the issue lies with an open “session_start()” function being called unconditionally, meaning that the plugin or theme is trying to initiate PHP Sessions everywhere on the site, instead of strictly where it is needed. WordPress does not use PHP Sessions, and as such sessions should not be initiated on the editor pages.

The problem occurs only when wpForo is activated. I could say that it is a conflict between plugins, BUT the problem also happens in my empty-no-plugins WP test site.

The only thing i will (try to) do is ask my hosting company to check if they see any more details for the original error at the top, since my debug.log is empty.

The first thing to do is contact your hosting company and ask the hosting support team to check the following points :

• Make sure your server is running a recent version of PHP and the cURL library.
• Try to increase your Server Memory Limits settings.
• The cURL error can be a dns related issue. Your hosting company might need to switch dns configuration to OpenDNS : https://www.howtogeek.com/164981/how-to-switch-to-opendns-or-google-dns-to-speed-up-web-browsing/
• Ask your host if there is some limitation with wp-cron, or if loopback is disabled.
• Ask your host if there a firewall or security modules (e.g. mod_security ) that could block the outgoing cURL requests.

I don't see any information related to editing files in the post you've mentioned:

https://wpforo.com/community/how-to-and-troubleshooting-2/noticed-some-missed-wp-cronjobs/#post-19452

It is there, here is a quote:

Callback to site failed, this may prevent WP_Cron from working, as well as prevent editing of themes and extensions. An error occured: (0) cURL error 28: Operation timed out after 10001 milliseconds with 0 bytes received.